Hi everyone, first post here, suuuuper excited about this project after just stumbling across it a few days ago. I had the same problem, especially since I'm using a Steam powered version of Doom 3, which has the doom 3 folder buried way down in the steam folder. Once I installed the patch and thief's den there i had no problems launching it from the mods section in doom 3, although i'm having problems running the command line/changing the desktop shortcut to run thief's den.