I experienced the same bug as Escheton. When a Treant smacked the ground, everyone stopped moving except one little swordsman. The rest of the game is still going, but none of the other characters move.
Two bugs I ran into: You can waste your level up on an already maxed out sword and when I was in 3-3 on level 5/5, I killed the last cactus dude and then the ruby disappeared. I was totally stuck, there wasn't any way out of the level.
Ha ha, I was on like floor 30 or something, and it just go stuck. Then it says that I instantly level up continually. As soon as I'm done clicking to allocate my points, it levels up again. I'm level 133... 134... 135...
The only real issue I have with the game is that you don't know which orb will affect the enchanted doors until you're holding it; then they show their color and slam closed. I'd also like to be able to look around the level a little (outside of the little guy's viewable area) to do some planning. I really enjoyed the game, though.