Crash on loading a save

Recently i have been experiencing crashes loading from save. The load screen  will come up and load for a few seconds then crash to desktop. Ive modded the game so the map has a lot more stuff in it and i thought maybe my pc just couldnt handle the load. So i went from the largest map to second biggest and cut my major AI players from all to 3. Again it crashed on load from save.

What i noticed was that it crashes after i complete all research( modded so i can complete all research in about 30 turns). In both games the saves i have issues with are the ones after this point. It will not load from my own save( i usually alternate between two) or from auto saves.

Then this morning i found something interesting by accident. I loaded an older save of the same map  and it worked. No big surprise. I exited the save to main menu and then loaded my newest save...and it loaded! I didnt play at that point. I just now tried again and again the exact same thing. It will not load from the most recent save unless i load an older save and then load the most recent after.

While im glad i have a workaround, any ideas on why it would do this?

Relevant PC info:

Intel i7 860

8 gb ram

GEforce GTX 650 1 gb ram

Win 7

Did the general suggestions page with steam and file integrity and checking path. Didnt do a complete uninstall/reinstall.