Kanto works, Hoenn doesn't.
Please take a look @Eggplant
If you fix it this weekend i'll gift you a 7 day donator status.
EDIT: Just checked with my limited mod knowledge and there is 0 reason why it wouldn't work.
The mod is structured exactly described like the mod post instructed, the structure is virtually the same as the kanto one which does work, the bgm codes are correct for the area, i've manually downloaded the tracks converted to OGG and basically redid the entire mod and it still doesn't work.
I think it's something wrong with the programming of Hoenn itself.