I believe that the autosave saves a copy just before the start of turn 0. It than writes over it the next turn when you choose your starting location, but you could like write a batch file to save it somewhere (or to multiple files e.g. Mygame1, Mygame2..10 when you start a new game (i.e. click an icon to do this) then load those as desired: or just copy and paste it manually...then use that to copy and paste again to new files as much as you want if you like the map.