I had an odd and quite frustrating bug happen tonight.  I saved my game, quit, and when I came back into the game, my army that had four squads suddenly became one squad and three singletons!  Even stranger, during the turn on which I loaded the game, the correct number of units still showed - yet their stats were those of singleton units, and the unit count followed suit after hitting the end turn button.

Pretty much torpedoed that game, considering the strategic situation.  A very frustrating bug.