What a long demo! I've been playing for an hour and I think I'm about 2/3 through it.
I would love it if you keep the original Hungarian and just make the subtitles last a little longer - it would look weird dubbed, and it'll lose it's charm. Plus, my mom's side of my family is from Hungary, and they'd love to see a game in Hungarian

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Here are my thoughts so far:
What I liked:
-Excellent quality - videos look wonderful, and the static pictures are lovely as well.
-The feature of having a printed letter version on the handwritten letters is one every game should have. Not all of us have perfect eyesight, and not all of us can read joined writing.
-The acting is pretty good. So far only one character seemed to over-act.
-The map is a must, and it works well. I would've liked written names on it as well, though, as the library and the hotel looked pretty similar (or maybe just have a picture of books to represent the library?).
What I didn't like:
-There's too much freedom. It happens alot in games like these that show a real location - you can see everything. Though it looks very nice I would've liked to be led by the hand at the start of the game. Take me to the tourism office at first, and only then let me roam around. I was walking around for a good ten minutes before I checked the map. Also, half the times I was walking I would end up in front of a doorway I couldn't go into, which was frustrating.
-Like other people said - too much panning. It's a weird sort of panning where you need to place your mouse as close to the middle of the screen as possible to be able to move comfortably. This game could benefit from free 360 panning with the cursor fixed in the middle of the screen like in the Kheops games. And then make the screen fixed when you enter a close-up, or need to solve a puzzle. It makes for much faster movement.
-Too much reading - this is just a demo and there are already five letters and one journal! It's tiring. The letters also seem overly long, but that may be just me.
-At the start of the game the main character will urge you a couple of times to get out of the room. It happened way too soon. I had just begun playing with a new interface to get used to, and two letters to read in the inventory. The last thing I want to do is get out of the room - I want to explore my options, read those letters, explore the room for anything of interest and only then get out.