Your save seems to be broken though, Egypts capital had a population of zero! This caused loads of division by zero errors, as no city should ever get to zero population ever. I fixed it in worldbuilder for you, get the attached save. When something like that is wrong then other stuff might also be wrong in your save. There was some SVN revisions before 10806 that corrupted saves, you may be a victim of that. Also, update your SVN to 10822 or newer to make it through the end turn without the game freezing. Edit: I played your save up to turn 401 (40-50 turns or so) without errors, so the save might not be so bad off as I first thought. Don't worry, the save I uploaded is on the same turn as you were in last.