Yes, all the dragons except Vulak have gone down.
Call me a masochist if you like, but I enjoyed Kreizzen (sp?) the most. We wiped 3 or 4 times before we got it figured out. The effect is butal and I'd place this one as the hardest aside from Vulak.
A few were too easy, but I don't take notes and can't remember which ones.

One has been fixed because he was slowable. There were two in a large room with 3 dragons that seemed too easy to me also - they were on the sides of the room. The middle one was normal though.
Maybe Jeido or Magoo can list names?