Hi, i'm back from DC, and will try to help if I have had the problem.
Here are problems I've had: game periodically quitting before song load, game quitting if you press F1 to select song difficulty (not always, but FOF sure doesn't like it.) Also, if you press enter more than once at difficulty selection, game may quit. Yes the game quits a lot, but if you open FOF from within a window (as opposed to when you open it from a desktop shortcut), you can quickly reopen it just by pressing enter. Plus, FOF remembers the last song and difficulty selection, and doesn't take long to load.
I have not had the parts not moving problem. Could you give more detail, such as are individual files not moving, or some of the data in the files? If individual files, which ones? Was the download corrupted?
BTW, I haven't tried getting the mp3's, so I was just wondering, is it the entire song, or just a part?
So, 4 people have tried FOF?