Many times, when I load a previously saved game, I get the scenario beggining dialog. I mean the buttons to choose side, start game or cancel. If I had a unit selected, it shows its remaining APs, but cannot do anything with them, they are just wasted.
I've also seen that if a damaged unit was activated before saving, when I load the game the rally button is disabled, even if I have APs enough to use it, and it was enabled before saving.
I can replicate both behaviours easily most of the times (always?).