This bug seems to still be around - if you use a spell like pillar of fire on units in the strategic map and they drop to zero health, they'll stick around. I was unable to attack stacks that had been damaged in this way and I wasnt able to end the turn either.
I was able to save and reload, which fixed the issue - so far I've ran into this twice with Magnar I'll see if I can do a before and after save if it happens again as it's fairly predictable when it happens
