Does anyone else get this?
When I click on something, an imprint of the background seems to get stuck around the cursor. This also happens when I move an item around in my inventory.
It's hardly a game breaking bug, and the game seems to run fine overall. Still, it is kinda annoying since you'll notice it pretty much all the time.
If anyone knows what is causing this or more importantly, if I can fix it, I would be very thankful!
My system:
Intel Core 2 Duo 6700 @ 2.66GHz
4GB RAM
GeForce GTX 260 869 MB RAM (latest drivers installed)
Windows Vista Ultimate (64-bit)

I notice this off and on with my retail copy :/, might be the High Res mod I have installed

I had the problem before installing the high-res pack.

I'm having the same problem immediately after installing the game. No mods or anything.
Intel Core 2 Duo
Windows 7 64 bit
GeForce 9800 GTX
edit: I got around this by running the game with the -no3d command line switch.

Same here. With or without HiRes patch.

Figures - now that its mentioned I am seeing it more often in my game :(. It likely has to do with color depth or the like.
I tried to test out windowed mode to see if that would get rid of it - but I could not get a reliable windowed mode working. I reconfigured the High Res patch to be lower than my max resolution, started it with the -windowed option.. and it was a disaster.
With or without the -no3d switch the interface is laggy and FPS drops to single digits. With the -doublebuffer switch on that switch it is even worse, with just the doublebuffer switch there are black boxes everywhere (textures not loaded properly).
So windowed mode is out for a fix - hopefully we can figure this out, now that I notice the cursor graphic anomaly it is irritating me.

If you set the game resolution to a resolution that is not supported by your video card you can get some unexpected results. Make sure the resolution you input when installing the HR patch is a resolution your card supports.

Thats not causing the transparency bug w/ the cursor, running at native resolution on my computer causes the same thing.

Try setting the path in the game icon to "C:\Program files\GOG.com\Arcanum\Arcanum.exe" -doublebuffer
That has been known to fix some graphics problems as well. . . =)
Edit: or what ever your install location is . . . just add -doublebuffer after the path to the exe outside of the quotes

Tried doublebuffer and no3d switches, they decreased performance for me for some odd reason (maybe because I tried in Windowed mode - will try FS mode w/ them but I think performance will still be sub-par considering how much of an issue they caused in Windowed mode)

Hmm - first time I tried the switches I had horrible performance. Tried them again (had to use both of the -no3d and -doublebuffer) and I no longer have the cursor transparency - the overall gameplay seems a bit smoother too.
Having way too much fun replaying this though :p

Thank you! This fixed the problem. I tried adding "-doublebuffer" first, and it made the cursor turn invisible (!), but then I added "-no3d" as well, and everything looks and runs perfectly now. :)

Indeed. I remember buying it at K-Mart within a few months of release. It's still the best $40 I've ever spent on a game.