A few comments were made that maybe, just maybe, a little guide of strategies would be helpful for this game.  So, I thought, why not share some hard won secrets with those of you who wish to torture yourselves.

This is NOT a walkthrough.  Hopefully, this will be a guide to help you get past some difficult situations.  Some comments here are excerpts from e-mails and posts(Quotes are in " ").  A special thanks to Shirley and Cheryl for playing the game with me, letting me steal their quotes and adding strategies that I missed.
 

Points to keep in mind while playing:

1) Always try to sneak past your enemy.  When they turn away from you, you can follow by walking.  Watch your enemy to observe the path that they walk.  This is their motion area.  Walking up behind them and whacking them on the head before reaching the end of their motion area can kill most.  Some enemy cannot be killed without taking some damage to yourself.  I usually leave these guys alone.  You know them because they shoot you before they even turn around. “If unable to sneak by your enemies, you could also try to run like crazy to avoid bashing and bullet fire. There are a very few parts where it is good to run after you have stood and scoped out the enemy and decide that may be the way to get around them.”

2) Use your "A", "D" and "S" keys to change your point of view.  If you don't, you'll be complaining throughout the game about the lousy view angles. “Using these keys separately or together will give you lots of various good camera views You can also use your arrow keys with the "S" key as well.”  Well, you'll probably complain anyway, they can be awful.

3) If you stand still and are standing outside an enemy’s motion area and he is walking/running towards you, he'll more than likely just turn around and walk away when he reaches the end of his motion area.  So be quiet, do not panic.  Corners are usually safe places to sneak to.  Boxes are also good.  Enemy will usually ignore you when you are on a box or higher up.

4) This is a glitchy game.  I ran it with DirectX8 and every so often it would dump me to desktop.  This usually occurred when I was loading up a saved game after having played for a while.  I was never dumped while in the middle of playing and only happened about 8 times.  Others were able to play with DirectX7 but had to load different drivers.  Another player could not continue the game using DirectX7 and a Voodoo graphics card.  The graphics were just too bad.  See below for more detail on this issue.

5) Camera angles are sometimes askew.  When this happens, use your "S" key.  You can become stuck in walls, fall beneath a lake, a conveyor belt and the like.  It's a fact in this game and you'll get used to it.  If you get a really bad camera angle, then you probably aren't supposed to be where you are.  Reload or extricate yourself.

6) This game works best with default keyboard controls.  They are similar to other games of this genre, such as Tomb Raider.  The game manual says that a game pad can be configured but that the default keyboard controls work the best.  Again, see below for more detail.

7) This is a linear game (it follows one path).  Your exit will be somewhere in the near vicinity.  Most of the puzzles in this game are actually figuring out where the exit is.

8) Saves and health.  These were my main concerns with this game.  I wanted more health and more saves.  I finally realized that the makers gave you enough health for each mission/area.  I would save up to 4 healths with Jekyll just to lose them when I became Hyde.  It's not worth it.  Figure out the level and get out.  As for saves, well, save whenever you see the pocket watch icon.  You can walk back and forth between some levels and kill baddies and return right away to another level to save.  That baddie will be no more.  Example:  You enter an area.  There is a bad guy in front of you.  You sneak up and kill him.  Go back to the previous level.  Turn around and reenter your current level.  You will get the pocket watch.  Save your game.  That bad guy is gone forever.

9) When jumping Dr. Jekyll or Mr. Hyde, use the "S" key to check that your sight is lined up for a good jump trajectory. “Having your line of sight perpendicular and in the middle to where you want to jump is helpful.”  This is very important in the caves at the end of the game.  It will often look as though you are going to jump down or up to a ledge just to find that you missed and are now dead.
"I think I finally learned how to get Hyde to jump better tonight...... I now line him up to where he is going to go and then as he is moving I WATCH HIS FEET and hit my jump key just before the edge.  Works much better for me.  I WAS before watching where he was going to jump to and my timing was way off a lot of the times."

"They left a lot out in the manual of how to get Jekyll to do his fancy moves I think. I didn't know either that while he was hanging there he could move right or left."

10) Quite often your way is hightlighted for you.  Look around for very bright objects or objects that seem to have a beam of light on them.  You can usually interact with these or it is the direction you should take.  In the Caves/Corridor level, the green lights in the library room are overly bright as a hint and some of the ledges in other rooms are lit up to hint the direction to take.  Street lights will also signal a possible exit or interaction in the quay/dock areas.

11) I found that the game played better and crashed less if I disabled my virus program and shut down unnecessary programs while I was playing.

12) The game style and atmosphere are the best part of the game.  The well-developed characters add to this feeling.   When you play Dr. Jekyll, you are a reserved gentleman.   When you play Mr. Hyde...well, read this:

"HUZZAH!!!!! I'm Mr. Hyde......and I'm one mean ol' snarling not to be messed with S.O.B. bwahahahahaha.  Trouble is when I lost my good looks and great (ahem) personality, I seem to have also lost a few brain cells too"  "I'm running around snarling, growling, slobbering, and ready to go."

"I also find it strange that he (Hyde) can jump better and it seems further from a standstill walk/jump combo than from a run/jump combo. It defies gravity."

Hyde will need to throw rocks, boxes and barrels at different times during the game.  "When you are Hyde, if you pick up anything to throw there is an infinite number of things to throw at the time.  You throw your item and magically there is another one to replace it if you just wait long enough."

13) At the beginning of most levels,  there  will be a cutscene.  Watch closely as there are clues shown as to which way you should go or things to accomplish in the level.  Some of the cutscenes actually show you the way to exit that level.

14) Take a peek at Jekyll's diary  in the options menu once in a while.  There are clues to what Dr. Jekyll believes he needs to accomplish to find his daughter and it's just plain interesting.

15) There are no cheats for this game at this time.  If I ever find some, I'll try to update this guide.
 

Here are some hints for confusing areas:

Desk in Lab/Lecture Hall (blocking the way to the kitchen area)

"I got the desk moved only by accident. I had been pushing, shoving, jumping up and down, even tried beating it so badly that I thought I was going to make some pulp for paper out of it. Then I tried crawling under it on the right (high side) so that I could lift it. Beating it from over there worked".

I, myself, got on top of it and used the action key.  It took a few tries, but it will work. You just need to move Hyde around and find the spot that triggers it.

Towers

At the start of the towers level, you must use the crank from your inventory to lower the cages hanging from the ceiling.  It appears that nothing is happening, but if you turn Jekyll around and look, you'll see that the cages are actually lowering.  I believe that if you turn up your volume, you might be able to hear them as well.

Opium Den

You get around the opium den by sneaking up and killing your enemy one by one.  You must be Mr. Hyde to make the jump to the dragon's head, and yes, it does work.  Make sure that you are lined up properly and take a running jump.
 

The First Quay after Cut Scene

Go up the concrete ramp in front of you and turn left.  "Run or sneak past the sniper and guards to the alley/doors leading to the rail yards.  It's really more of an alley than doors, so it just looks like a dark area. And a neat thing about this area is that you can go into the next level save your game, return to the docks and kill off some of the guards one by one and go into the next area and save your game after each one. You'll come back here later, so if some of them are dead it'll be easier on you (at least the two or three by the exit there). The same holds true for the next level (rail yards). You can kill some of them and return to the dock/quay, then return to the rail yard and save your game. It's like being able to save when you want."

The Print Machine in Warehouse

"To get through the printer's I used the printer itself to get by those nasty robots. You will have to climb up, walk a little ways, watch the timing of the robots, climb down, go a little further and climb back up. You need to get to the other side."   Don’t miss an important clue here.  “Be sure to look up in this area.”

Barge (after rail yard and conveyor)

You can use boxes to hide and kill thug or just run and jump onto barge. Once there, pull up onto top of barge. There is a brick wall/archway in front of you. Walk Hyde off the left side of barge (you can see a box on floor of barge). Use box to pull up onto top of barge on other side of wall/archway.  Don't jump down to the front of the boat where there is a guard with a gun walking around. You aren't meant to be there.  Instead, run and jump to barge steerage roof and keep running and jump up and through the window. The game saves automatically here and your fight with Yang starts.

Mr. Yang

To kill Mr. Yang you must run up when he is unprotected, whack him and run away when he becomes Blue Bubble Boy (BBB courtesy of Sassy). He will not hurt you if you are the right distance away. If you are too close he will bump you with bubble, if too far he will shoot you. Just the right distance and he will do nothing and stop bubbling, and then you can attack. It takes about 7-8 whacks to get him.

The Railyards

Walk up the spiral steps to the control tower.  Even though you are being shot at, they shouldn't hit you as long as you keep walking.  An “alternative route to tower is to jump from the tall boxes to the left of it. If you get in the corner behind the boxes there is a movable big crate that you can push forward along side the tall boxes and use it to get to the top of boxes. Then you will need to do a run/jump to the upper level of the tower.”

Conveyor

I just ran down the length of the conveyor and jumped to the walk in front of me.  I then walked around the glass and whacked the guard as he slept.

Green Isle and Tracks

If you opt to use the island platforms, you will get to one that has a tall spire on it.  This spire is here to make it hard to jump to the next island platform.  You must use a running jump from the right side of the platform, just missing the spire, to make this jump.  It is not easy and will take a few tries.

"I ended up taking" the "route down the tracks, because I just couldn't make the second set of Green Isle jumps. And that was a hard route too"
 

Robot Warehouse with Claw Machine

You can either walk underneath the machine and make a jump when you are almost at the end, or try running zigzag past the claws.  I found walking then making a jump much easier.  When the robot's back is turned, walk calmly, just left of center under the machine.  When you are close to the back set of claws, jump between the railings into the next area and run past the robot.

Electric Chair/Book Room

Some folks have had problems getting Jekyll to sit in the chair.  I walked up the right side steps, and then approached the chair from the side, not the front.  Hit the action key and Jekyll should stand in front of the chair, and then sit. There seems to be a known major glitch here in the game for some folks and if you can't get him to sit, you might have to reload a previous save or uninstall and reinstall the game.  (Of course, move your saved games to another folder if you do that).  Manipulate the robot to pick up the book, using the symbol on your upper right screen as a guide, and return to the robot's starting point before the blue air runs out.

Cemetery Step by Step

This will get you to Stevenson's tomb. I don't know if it is the shortest, but it's pretty fast. You won't be stopping to pick up anything other than the key and the doll. An intersection can be 2,3 or 4 way.  You will miss a lot if you use these directions.  You may want to play and look around for a while before using them.

From the start of the cemeteries.
Get the key from the shack just to your right at the start of level
(You will be running the entire way)
Start running
Right at 1st intersection
Forward at 2nd
Left at 3rd and run through the gate
Next area
Forward at 1st intersection
Left at 2nd
Forward at 3rd
Forward at 4th
Right at 5th
Run through archway past vamp in purple
Next area
Left at 1st intersection
Run all the way to next gate and through
Next area
Pick up Laura's doll at intersection
Go back to gate and turn around to face the cemetery
Right at 1st intersection
Left at 2nd
Right at 3rd
Forward at 4th
Right around corner by purple vamp
(You can only go right)
Run through gate
Stephenson’s tomb is the one on the left.
Remember, have your key ready, walk behind the vamp, use
the action key and jump into crypt.

If you take the time to go through the cemetary, take note of the names on the tombs.  If you check these names against the credits at the end of the game, you'll notice that they are the same.

Caves and Corridors

There are maps of the corridors scattered around the hallways.  The corridors are color coordinated, so take note.  Some hallways lead up and down and there is health scattered about as well.  Your purpose in this leve is to destroy 3 columns in 3 different rooms.  I had to go back and destroy a column I had already destroyed to be able to end the level.  If you have trouble finishing this level you might need to recheck to see that all your columns are still ruined.  To destroy the columns, use the rocks on one of the beams at the very top of the room and toss them at the center column.  In the Library, there are two steps.  You must whack the green lights to bring down the major part of the column and then assend to the top of the room and destroy the rest of the column.

End Scene and Boss Level Fight

When I played this game, I had no boss to fight and the game ended abruptly.  After speaking to other players, I realized that I had played some actions out of sequence and thus forced a different ending.  Following are two different scenarios, as related in e-mails.

NO Boss:   I climbed up as Hyde and killed one vamp and the other walked off the beam. I then walked around and broke all the beams with rocks till they were vertical (about 3 each). I had to climb down and then up again to get more rocks to appear and the vamp that had fallen off had to be killed as she was at the bottom walking around. After I had 3 beams standing vertical and the green miasma beam with the cage was semi-broken, I descended again and went and got the Book.  When I reenter the Dorm for the final battle as Jekyll, there must be nothing for the Boss Vamp to stand on so he falls into the pit.  I calmly walk up the beams and collect my daughter.

"Now I know why our endings were different............It's the book!  When you said you had the book I thought you had it before you went up the beams, not after.  I grabbed the book befor going up the beams."

Boss Fight:  "When the level starts and the Howlers start at ya. I found it easier to go counter clockwise to the green lite ramp first and stand there and wait then start my way around then clockwise. This way you can grab the boulder on your way to the next ramp as you head to it........it also made it easier for me to remember that I started throwing rocks at the first ramp from the greenlite one. Just throw one rock at each ramp as you go around and repeat that 3 times. You may have to wait for the rocks to fall from the ceiling as you finish your last toss going around once. I'm not sure but it seemed to me that the rocks would not fall again from ceiling until you finshed tossing 4 rocks on a once around trip. You are safe on the beams...... I would have Hyde stand there at the end of a beam facing the way to walk clockwise then use my s key to watch the Vamps route and just walk off to grab rock as they just passed me, and walk to the next ramp and leisurly line up my throw and toss and then wait and walk agian. Have full health to start with, Jekyll has a medikit in his coat you can use..........you shouldn't loose any health til you start tossing the 3rd rock onto each ramp and they start toppling.... then it get just a little harder."

A Few More Points about the Game

Funny Glitches and Easter Eggs

At the beginning of the cemetery level, enter the shack on your right to get the key.  If you look left you'll see a barrel.  Whack the barrel a couple of times and you'll get a puppet Jekyll holding a sign that says something like: I love (heart) Mahara.

"had one of the craziest things happen to me.......... I was in the Cemetery at one of the gates and I hit the 'yes I wish to continue' key and when the level loaded there was Jekyll, and this was like in the blink of an eye, standing there with his head spinning round in circles like something out of the Exorcist........ I thought I was hallucinating.........But I know I saw it"

"I had a funny thing happen too the other day. I was on a box and tried to jump down real close to a guard and was gonna whack him real quick after the jump..........well instead of landing close to him I landed on top of the dude. It was funny. I just stood on top of his head and whacking him from up there did nothing so I just started spinning Jekyll around like a top on top of this guys head and then started jumping up and down on top of him. What a hoot. Then I fell off and of course he shot me."

"Just like the glitch with the moving sidewalks, I was able to walk all around under the lake. Really weird! Had a real rough time jumping up on that last railway car, Hyde kept falling down between the cars and you could see him running there like he was pushing the train."

"I get a little weird flashing in the Lecture hall every now and then, but nothing major, and if I get Jekyll stuck to close to something and he can't move the screen jiggles, but I don't think its a glitch, just something the game does........... At first I thought that was snow coming through the ceiling in the Lecture hall, but looked up at the lights today and *dust* is probably a good description Nancy. Looks real cool. I also like when you stop Jekyll from running and you get the little poof of smoke or dust or whatever coming out from behind his heels."

"Sound is real good too. It was weird yesterday like I was picking up some sort of someone else's radio signal or something.........strange. But today sounds great. I'm using headphones. Like Hyde's snorting and snarling."

Not so Funny Glitches

"I have a question about the display settings. I want to set it at 1024
but every time I go in there it resets to 640. Any way of keeping the
higher resolution. Since I only have a measly 16 meg card on this PC, I
can only do 16 bit graphics."

"My graphics are really glitchy. While I was hunting down water to put out the fire I jumped up on the counters on the kitchen. I was able to jump right up into the cupboards and the stove vents. Also my camera gets spasmodic on me occasionally. Looks really weird. And I keep getting hit by invisible lunatics."

"The game keeps crashing to the desktop and resets a lot of my settings
when it does."

"After replaying several spots countless times so that I could save my medikit potion for when I felt I really would need it, I find that it is not in my inventory now.  Neither is the ether. Never even got to use it."  This never happened to me, but it is something to keep an eye open for.

Likes

"moving the saves from the J&H file is easy.  They have a folder called SAVES and it looks like it has every thing there you need all at once."

“Has good confirmation when you save a load so you don't do something you shouldn't accidentally do.”

"I did full install and just accidentally found out you don't have to have the CD in to play the game.
I like the camera views you can get when you hit the s key. Have you noticed that the camera views can be changed with your arrow keys besides the a and d keys.
My walking stick has one hell of a long reach for bashing folks. And most of them go down pretty easily with just one whack.
Getting used to moving the Dr. around and jumps and strafing while holding on to edges are getting easier. He's actually not a bad jumper compared to a few other games I've played.
The voice acting is good so far.
I like the rain effects.
Use of lights and lighting is great.
Saves take up hardly any room at all, so moving them before you write over them takes up very little HD space.
Like the inventory system.
Hot spots are fairly large and items to find are pretty easy to find so far.
Graphics are cool, not outstanding but pretty darn good.
Atmosphere is good.
Keys are easy to learn."

Gripes

"Only 6 save slots
The save often suggestion in the manual is a joke. I will only let you save where it wants to anyways most of the time.
No backwards for Jekyll......... the down arrow only turns him around. When I'm being attacked it sure would be nice to back up so I don't get clobbered. No keys for strafing either, can only seem to move forwards, which makes lining up for jumps take longer.
The down arrow that turns Jekyll around doesn't do it in precise 90 or 180 degrees turns.
No quick save
Can't rebind the shift key to get him to run.
I keep getting very dizzy from the way the camera keeps swaying all the time when you move. When Jekyll stops moving the camera keeps moving slowly till it stops in the direction he's facing.
Sometimes I lose track of where he is when he goes behind a wall and I end up getting whacked or something cuz I can't see him.
You seem to lose a whole lot of health too quickly when some one hits you or you fall not very far."
“Have to exit game to rebind your keys.
No Alt/Tab so you can check WT or this guide while playing the game. You must exit the game to get to other programs.”

A Word about Direct X

This game works best with Direct X8 or 8.a.  Below are some problems encountered when trying to use X7.

"Up until this point it was bearable but here there is no way the game can be played.  DX8 was known to have some problems with games that came out before it was available. Plus with a v3 card , DX8 is just not compatible. Dreamcatcher lists this game as incompatible with winXP which is surprising as this game is not all that old. I tired every compatibility mode and it kept locking up."

"I'm using DX7.a   I'm also using the *official* 6.5 drivers for it.
I switched to this driver when Atlantis 3 was giving me so many fits. Before that, I think I was using the 7.58 WHQL drivers, which worked for all the games I played except A3.  I'm having no problems when I save, and graphics look and act good."
"I set my res to 800x600 when I first started and when I was looking in there today it was back to 640x400.  Seems like you may have to set your RES every time you start up the game. Phlooey!"

"I have a voodoo 3 card but I don't know what drivers they are. I know they are pretty old but have worked great for games where others have had problems with latest drivers so I am very reluctant to change. Since the company that made the voodoo card went out of business the V3 and DX8 are not the best together. On my XP machine, I have DX8a. but, no matter what compatibility mode I tried, I could not get Jekyll to work."
 

A Word about Gamepads

"I did notice in the manual that it says a digital gamepad won't work right with the game. You need to use an analog one."  "I wasn't sure what kind I had so I'm just using the keyboard."

"I am having a problem with programming my gamepad. I am pretty sure I did it right but when I go into the game I can't use it. The goal here is to be able to use both the gamepad and keyboard at the same time. The gamepad when programmed is a keyboard emulator thus you can use it in games that don't even have gamepad support."

"I unplugged my gamepad. It is both an analog and digital as it was so
annoying to uncheck this especially as I have to restart the game after
each save opportunity and I will save whenever it allows."

"You have to exit the game to reconfigure the controls. Also in that area if you have a gamepad on your machine every time you launch the game you have to go into controller options and deselect use joystick for movement."

“I had no problem with rebinding my keys, in fact I found it easier for me to use my own settings. Just wish I could have rebound ALL of them.”

End Game Walkthrough:
http://www.gameboomers.com/wtcheats/pcJj/Jekyll_Hyde_End.html

Last note:

There are probably many more questions, but as long as you keep in mind that the purpose of this game is to just keep moving forward toward the end and finding your daughter Laura, then you'll always know where to go.  The caves are the exception; it's just one big puzzle.  It is also the end of the game, no more moving forward.  Good luck!

GameBoomers Walkthroughs and Solutions