<<Not sure what it is exactly that you are trying to do, but if it is just a Transposition of all the instruments for a certain section, you can use the Bar Settings to change the key of a song at any selected bar. >>
Sorry, Mac. I didn't make myself clear. I was not changing keys just dropping an octave in some sections of the song. In some other programs I have, the transpose function includes octave changes also. I was only working on the melody.
Update: There is not a good way to do what I want in BIAB, but here's what I came up with:
1. If there are only a few changes, just do those manually by moving the individual notes in notation edit view.
2. If there are are a lot of changes, export the song to a midi file, open the midi file in a notation program (musescore, finale, etc.) and make the changes there.
3. Bite the bullet and make all the changes within BIAB in notation edit.
I'm sure there are a lot of other possibilities as well....