Well, that is indeed what I have going.

It sounds like you already have the IAC driver working.

In logic all I do is add the number of tracks that I need for a given song and set the midi channel to match what I have in BIAB. Make sure you enable the logic tracks to record. Then I choose the appropriate softsynth or patch.

I haven't tried anything as sophisticated as program changes. When I arrive at the ensemble that I like I save the Logic project with a name like "BIAB - Desafinado".

Good luck!