Try this:
http://forum.shrapnelgames.com/showthread.php?t=39744
Its a program that backs up each turn file allowing you to reload past turns.
You could do this manually but whats the point of having a top of the line computer if you have to do the work for it? I should say I have not used this program, I guess too many rogue-likes have instilled a fearlessness towards death
