ZeroZero, you said that dungeon layout is found on a dungeon disk from locations $002 to 201.
However, consider this chart:
![Image](http://img19.imageshack.us/img19/6040/hexdungeonmap.png)
The byte for 21N 21E is $1e5, NOT $201. There's 28 bytes unaccounted for.
Quantum Reality says there's a lookup table somewhere.