Some more random observations (and I'm not 100% certain if those are patch 8-problems or if I simply never ran into them before):
- AI behavior at the very start of the Nere-fight can be off and result in unwanted consequences. Meaning after you blow up the cave-in and then stand near the center of the area to wait for Nere to start moving and trigger his cut-scene, the Sergeant will move towards the cave-in area, step into the lingering fire-surface (from the explosion) and then auto-aggro. Which not only bypasses the Nere cut-scene but also will put Brithvar and his rebels up against the party as enemies, even if you talked to him before and agreed to aid him against Nere. I've had this happen twice in a row in my current play-through and only on the third attempt did the Sergeant not step into the fire surface and thus didn't aggro before Nere got a chance to come out of the cave and do his thing.
- Some NPCs and companions will not show up for a while when you first enter/move to a new region. They will be clickable and the mouse-cursor will change to the "talk to" icon and display their name if you hit the right pixels/area in the world, but their models will be missing. Happened once with Lady Esther and, more frequently, with Astarion on the Act II Last Light camp-site. Waiting for about 30 or 40 seconds after entering camp will usually make him appear in front of his tent.
