Game crashes when trying to save

I am playing version 1.00 of Civ 3 Conquests and I have had a couple games where, later in the game (mid to late industrial era) it will suddenly start crashing every time I try to save the game. It crashes whether I initiate a save personally or if the auto-save tries to do it.

I can start a new game and it saves without problem. Occasionally I have managed to load a previous date of the same game and play for one or two turns futher before it goes back to crashing. I have not upgraded to version 1.22 because when I do the game suddenly can't find my CD (even though it's sitting right there in my only CD drive-see my other thread).

I don't know if 1.22 would fix this or not, but since I haven't had any luck getting 1.22 to work I hope I can at least get this fixed so I can play into the modern era! I WANT TANKS!!!

 

Something like around 25-28 GB free.