I'm interested if anyone has used Assignment Planner as a GTD app?

I've given it a cursory whirl after hearing that the program plays well with GTD. It does okay, but it seems like some hacking is necessary. I contacted the developer, suggesting s/he create a GTD app from the AP code. Developer's not interested in creating and then maintaining yet another application, but is interested to know what modifications s/he can make to AP so it's more GTD-friendly.

For those of you hacking Assignment Planner (or interested in doing so), any suggestions?