When I met Edowin's group, I convinced them to attack the owlbear. During this fight, I noticed several issues that occured:
I loaded and attempted it about 5 times. Every time the battle started, Astarion would teleport behind the bear cub, as if he had climbed up the path around the back, instead of walking through where Edowin's followers meet you in the cave. This occured even when I tried leaving him at the cave entrance by ungrouping the main character from the party and approaching the owlbear with the main character. No idea why he is teleporting, but it made him receive priority to be attacked during the fight, since all other party members were not within sight of the owlbear yet.
I approached the owlbear with my cleric after casting Guidance. When prompted for a choice, I chose Anmial Handling. I required a roll of 12 i think, and I rolled 18. I didn't see any mention of disadvantage during this. Yet rather than having any additional dialogue options, battle immediately commenced. Once again, Astarion had teleported immediately behind the cub. even though he was next to the rest of the party and Edowin's followers. I had approached the owlbear with main character solo. Same thing happened though when I approached with Gale solo.
Finally, after deciding that the animal handling response likely isn't working (or it is working as intended), i just commenced with the fight. Astarion killed the cub. Once it was the owlbear's turn, the cinematic for it screeching played, and the screen went completly black. Combat was still in effect, and I could end my turn with spacebar. But I was unable to do anything, even going to the ESC menu didn't bring it up. (well it did, but screen was black). Ending my turn still allowed game to progress, as evidenced by Edowin's mage casting and hitting the owlbear sound occuring.
So there are several bugs within this fight at the moment I think.
