Civ IV fixed, then broken again
Two days ago I decided to install my old copy of Civ 4 on my new computer (Win 7 64 bit custom hardware). I found a tutorial on how to make it run, and it worked. I played it for a day, it crashed, but then it worked fine again. I played it yesterday, worked just fine. No crash that time. Saved my game and left. Today I open it up, and it crashed on load. It starts "Checking XML" and immediately fails. No actual error, just that it has stopped working. I have tried running it in all kinds of compatibility, and with admin rights (Even though I have UAC disabled) and it still fails to start up. Any ideas what happened, and how to fix it?