gummyworm: Sorry, I wasn't very clear - I've tried Direct3d AND OpenGL. Direct 3d makes the main menu look awful (as well as the game). Open GL looks much better, but if I set the resolution above 640x480, the texture go all freaky. Is there a way to resolve this? (glide wrapper didn't work either)
I'm using Windows XP SP3. Other people on the forum are having the same problem I was. As it turns out, you just need to kill Main.exe after exiting the game (it continues running after the game closes) So that issue actually had nothing to do with compatibility mode.
Please post the solution if you figure this out as I am having the same issue. Direct3d looks horrible, and basically doesn't work.
I just saw this on another page. If you use the command-line parameter "-nomultitexture" this is supposed to fix the flashing walls problem. I can't try this until I get home from work so I'm not sure if it works or not.
This in fact worked for me. No more flashing walls.