I stealthed into the room just before the stairs at the end of the first level of the castle and killed all the enemies there. The named boss didn't spawn, and I continued on my way into the next level of the tower. I believe when I triggered the unlock of the door into the vampire's room on the second level I got teleported down to the first level and thrown into a cutscene with the boss (and all enemies in that room respawned).
Also in the wizard maze I used Misty Step to apparently bypass the puzzle I was supposed to solve (through some bars and then tap the button to open the door so the rest of the team can join). My quest journal didn't update to represent this, so after I got the gem, I still have the quest journal telling me to solve the puzzle (also potentially of note, I crit succeeded on persuasion roll to have him just hand over the gem so I didn't fight him).
I was unable to reach the long rest area in the maze (tried Misty Step and Spider Climb).
I was unable to use the teleporter I arrived to the maze to leave again (I wanted to level up to 5 before the last fight, but couldn't reach the long rest area on the map).
Several items towards the end of the maze area took so long to interact with I thought they were broken (I specifically remember the teleporter to leave, but I think some of the doors and loot containers near the end as well).
I hope it's not a spoiler to say that the long rest area is reachable providing you do so before you leave the maze. I got caught out because I thought maybe the final teleport would take you somewhere that gave you access and it didn't (I got killed - that long rest was really needed). I also had the very slow interaction glitch on that first time through - very tedious!
I never was able to reach the long rest area (unless it's part of the puzzle I bypassed). I tried spider climb and misty step when I had access to the stair area and still couldn't reach it then.
use your wiz...levitate self than misty step onto the raise platform. Have the wiz push the block out of the way, the rest of the party can now climb up.
Potion of fly could be an option too if you find one.
You can get yourself teleported there during the maze puzzle, you don't need to fly.: