BTW Annatar..would you be an administrator or something, to know so much about the game?
I'm just an old beta tester
Through many dozens of bugs and an awesome developers who don't shy away from explaining how things work, I picked up a few things. Even though I haven't released any mods, I spent a good several months after launch figuring out how everything works and fits together which is good not only for mods but for finding bugs. I'm also blessed/cursed with being able to remember all sorts of cra.. stuff. Much like an encyclopedia, only a walking and talking one.
Hope that sufficiently answers your burning question 
Regarding the compound ability thing, the ones already in the game show off pretty well how one fits into the other and should be pretty easy to follow. As I always recommend, if you're having trouble open your user.setting file and set showErrors to TRUE to get a more detailed error report from a mod crash, including the file and the line in the file that caused it - and feel free to post on the forum if you can't figure it out and I'll try to help.