I have been seeing a couple of bugs in Gaan-telet:
First bug I've seen twice so far. I have a screenshot of it, but not on this computer, so I'll have to repost it later.
Sometimes the next floor and previous floor staircases spawn on the same square. I don't really know the steps to reproduce, but both times I had it happen I was working on the "Oh Horatio" quest. It happened once on the bandit floor and once on the serpent floor. I was a bloodmage once and a sorcerer the other time. Not sure if any of those would affect it, just trying to be thorough.
The other thing I noticed was that mana potions seemed to be giving me double mana as a bloodmage. I have not tried this on any other dungeons though.
Last bug was a semi-visible vampire.
You can't see it, but my mouse is hovering one square to the left of my character. I knocked this vampire down to 1 hp, then traveled down to the first floor, whacked a lvl 1 monster for a level up, and when I came back the vampire's icon was gone from the map. I could still mouse over and get the 0 hp display you see, but couldn't kill him. I was still able to melee and fireball him, but it didn't kill him. Melee attacks still got retaliated as well.