This information on the levels is dumped from the ROM files. I modified the original dumping program which was written by Chris Moore with the help of info from Karl Stenerud.
General info is on the left with monster info on the right.
The monster delay is how long the game waits before the monster actually appears there. The delay time is given in frames. If you don't really know how it works, look at the info for level 1. If you remember how the monsters appear on that level and look at the delay time and positions then you'll see how it works. Level 102 seems to be the demonstration level.