I've had this happen to me as well. Particularly more often late in the game.

Well at least I am not alone. This has happened like 4-5 times in my game now. Also like MarvinKosh says, it's not repeatable on the same save. When I reload the autosave, I am able to continue but some turns after it happens again. Maybe it's some timing thing.

My current 1.20 game, getting close to Turn 300, has just started to get stuck. However, for me it is happening in the middle of a turn. Everything works except I can't move or attack. So, yes, I save and reload, but let's hope they can snuff this bug out.

UPDATE: After I exited the game completely, relaunched, and reloaded, I had no further problems.

Actually I do get an application hang which means hitting Enter or Esc doesn't do anything except vent my frustration.  Looking at my last debug.err it seems to happen right after a successful autosave.  Or I could be reading too much into that.

For me (on 1.2) when I press [enter] the game crashes. This has occured just as I passed the 100 turn mark.  I even received a note from Microsoft asking for the details! 

Unless someone knows a work-around for the 100-move crash, I will apparently have to stop playing until the 1.2 upgrade antidote is relesed. 

MY game hangs completely as well when it happens, no saving possible.

debug.err ERRORS are usually about stuff that wasn't found, but that doesn't coincide with the crashes. Generally theres a lot of warnings about "leaked" stuff in there lately, whatever that means.

I think (though I can't confirm it yet) that there's a bug with the autosave.  Think about it - autosave happens when you hit end turn, not when your turn starts, right?  And the problems start when turn processing begins, starting with the save if it's needed.

I disabled autosave, mashed the turn button and didn't get a hang.  It's not much of a test.  Still have to see how things work when the game's been running a few hours and I've actually been playing instead of mashing 'Turn.'

I remember that there was a similar autosave problem with GalCiv II if there wasn't enough memory available, so it's worth looking at even if it's just to eliminate that possibility.

I've seen this 3 times now and each time I found a unit running on autopath from one place to another farther away on a map but gets stuck running against a 'friendly' structure or town that the unit should have pathed around.  If you select the unit and get it to stay still (animated running action but not moving anywhere when you find it) then end the turn the game continued for me each time.

Exactly the same for me.  If I take Autosave off, I maybe get a few more turns.  But then when I go to Save Game it freezes and crashes, so it's the same deal.  Unplayable.  Is there a fix for this yet?  Or do we just wait for 1.3 -- my top priority for that patch would be to fix these major crashes; all else is window-dressing.  I upgraded to 1.2 from 1.02; now I wish I hadn't.  The fact that it's a great game when it works makes it even more frustrating.