I upgraded to 0.92 yesterday (coming from 0.90 I think; could have been 0.91) and started a new game. I noticed that after a while my sovereign could no longer attack enemy units (they were all monster stacks, no enemy factions). He simply moved to the same square (the "2" appeared to notify me that the square contained multiple armies).

I tried using the turn button, but that did nothing anymore.

I saved and reloaded the game (without fully exiting to desktop) and I could attack units again, though any stack I had attempted to attack before the save were simply untouchable, though I was able to attack them using a strategic spell. Other stacks could be attacked normally. After a few more turns the problems returned.

EDIT: wrong forum. I'll repost in LH support.