Suddenly, Can not Open

Well, I'm on my second play thru just a few years shy of a win and the game will no longer open. It gives a message saying I must have administrator privileges. I've not been playing as administrator because when I tried to do so, the game didn't recognize the campaign I was well into. At this point, I don't really care if I continue my french game, I've basically won, but if I now try to open the game as administrator, I get the window asking if it is OK to modify my hard drive which I of course check "yes" but then, nothing happens. I've tried twice reinstalling the game making sure everything in the "Sega" folder was gone but to no avail.

Any ideas?

Edit: Oh, yeah:

Win7
Available Physical Memory 5.71 GB
NVIDIA GeForce GT 545