The manual is identical to the PC-9801 3.5 inch version except for the front cover.
Dungeon Master for PC-9801 2.0a (Japanese) Cracked.hdm
Dungeon Master for PC-9801 2.0b (Japanese) Original.hdm
See also:
How to play PC-9801 / PC-9821 games under Windows? (Dungeon Master, Chaos Strikes Back and Dungeon Master II)
What is a PC-9801 / PC-9821?
To apply the crack, follow these steps (this applies to version 2.0a, version 2.0b is not copy protected and does not need cracking):