HELP! I haven't used it in a few months and now it messed up the old playlists! It endlessly rechecks the BPM and never saves it, and the overlap doesn't work AT ALL anymore, and if I try to move it, it erases again! And my catalog is never saved correctly. I reinstalled a couple times, same crap! Is there some hidden file in a registry I need to delete manually to restart?

That sounds like question for tech support.