hmmm, playing a new game won't delete your savefiles, at least it doesn't do it for me...
only thing i can come up with right now would be to delete everything from the game (all saves and the game itself - you can store your saves on an usb-stick) and then try it again to be completely sure that it's not due to saves or corrupted files. then download it again from f95 and if it happens again we know at least for 100% that it's not your savefiles. but it really is kinda weird, why shouldn't the game work anymore for ya? o.o.
ps: also clean ya pc from unwanted registry files. juuust to make sure. i'm no pro here but it sometimes helps ^^.
what OS are you using by the way? the game is made for win7 if i remember correctly.