I haven't seen this mentioned anywhere else so I thought I'd post it seperately here.
In the tunnel under the druid grove I used a "Pass without Trace" spell to sneak up on Brawler Gresh & his group. After initialising combat with a backstab from my PC it took me a turn or two to realise that my companions weren't involved in the combat, obviously still hidden. So I had them perform attacks to bring them into combat.
At this point Astarion would not follow the group or perform any actions, I could move him individually but he wouldn't enter TB mode. If I clicked attack then he would move up to the enemy, but do nothing. If I tried to get him to cast a spell, the sound effect played but he remained motionless, and nothing else happened. None of the enemies targetted him despite him being stood right next to them.
After finishing combat he still wouldn't follow my party or perform any actions. After closing & re-loading he was back to normal.
