You might be looking for bar by bar regeneration but you can't do that with Biab MultiRiffs as you loose your current tracks when it starts a new session with 7 new tracks.
You then choose one of those tracks and import it back into the Audio track of you original song as I described in an earlier post.
What I described with using the BB Plugin allows you to have all the separate tracks within the one instance of Biab until you are ready to transfer to the DAW by simple drag n drop.
When the Audio Edit drag n drop is fixed you can drag sections out of the BB Plugin directly into the Audio Edit track at any bar.
I'm sure the sync issue will be fixed very soon.