At B732 is the list of bits that determine if Maple shows up or not. One byte equals 8 rooms. Oddly enough, there are 3 region entries for maple, and 4 are defined as bitmasks. Also above there somewhere is Maple's appearance ASM. 41C6 is Maple's kill counter.
Hmm... Either that image is wrong or I had the bitmap wrong. I'm gonna look into it.