[.75 CTD] CTD on next turn after loading save created on a different machine

I don't know if it's supported or not, but since Steam stores the saved games in the cloud I thought I'd try starting a game on one machine and continuing it on another.  Both machines had .75 installed.  The game was started on a Vista 32 bit system and then saved after a few turns.  Shutdown the machine, booted my other one (my main gaming machine), a Win7 64 bit system.  Loaded the saved game, it appeared to load ok. 

When I hit the turn button the game crashed (the usual Windows LegendaryHeroes has stopped working message).

The debug.err from the crash is here.

The mdmp file is here.