venus,

Two of the forum members on GOG came up with a solution to fixing black characters on BS 4 which worked for them. To quote the one who didn't type in caps:

"This is how I fixed the black characters
Push the windows button + R (on your keyboard)
Type msconfig & click ok
Click on the "Boot" tab
Select the "Advance options..." button
Click the check mark next to "Number of processors:"
Select 1
Click "Ok" twice, & reboot your computer.

This will slow your computer down. (After all your only using 1 core on your CPU). Once you're done with the game, make sure to set it back to default."

Gil.

As an alternative, you can specify the processor affinity settings from Windows Task Manager, disabling all but one of the CPU’s; the game must be running to do this however.

Here's a how-to link -

Set affinity for a program via Task Manager

Utilities like Imagecfg and PsExec can also be used to alter the affinity settings (Imagecfg permanently alters the program, so you only have to use it once).

You'll find a thread describing them below -

Microsoft Tech Net Forums

BS4 was supposed to work with dual processors.
What it didn't work with were tricore, quad, and other multicore processors.

Now that Jenny mentions it - I do seem to recall having issues on my old dual core, but I don't think it was the exact same problem. I installed the v1.1 patch to correct it. If it's not been applied, maybe would that help.

Broken Sword: The Angel of Death v1.1 Patch

You can also try updating your video drivers if they're not current.

there is another patch out for the disk version on revolution uk site, its for the dvd & gog have replaced the exe file also.

once you patch the exe file you must start a new game

Wow. BS4 isn't that old and already on GOG.