I have one extremely basic question, and it's one I can't for the life of me find in the rules (I may have flipped through the book too many times so everything's become hazy...)

I enter a room, and a fight starts. The monster attacks...
now there's 3 options:
1. I defend successfully, defeat the monster, and can choose whether to fight the next one.
2. it's a draw.
3. I lose, and can't do anything else.

The question on everyone's minds (at least those of my friends and me) is, in which circumstances (if ever) can I just walk out of that room? (This one's really important to us, as we've often found ourselves fighting unbeatable monsters)
If I win, can I move past that room into the next unexplored one, or back into a previously explored one?
If I draw, can I withdraw, or do I have to fight the monster again?
If I lose, what happens next? Can I retreat? Flee?

next question: In yesterday's game, the first room we entered on the 3rd floor was "employee exit", which immediately opens a new room, and as we played the shortest game, that was Xykon's floor. What happens if a player gets defeated down there? How does he get out, if he can't flee through the exit?