I think I've got the issue narrowed down a decent amount. The user tracks feature seems to work flawlessly in version 3.00 (steam version), but I downgraded to 1.00 so I could use a script that fixes a few graphical issues.
When I attempt to play a user track in version 1.00, it works perfectly fine when I test it at the main menu BEFORE I load a game, but after I load a game 98% of the tracks cause a crash.
So basically, it's only doing it with the downgraded exe and only once I actually load a game.
Help would be greatly appreciated because I'd really love to use my own music.