Assuming that what you call "2nd Chorus" is a different set of chords from the main chorus, one way to lay this out in BIAB would be thus:

*1st 16 bars, use BIAB 3X Chorus command

*For that "2nd Chorus" just write out the chords in the bars after the first 16. Extend "End of Song" to end of those bars. Now you should have a song that plays the first 16 bars three times and then plays the next set of bars.

*Invoke a TAG ending (Song Settings) that is 20 bars long, Copy the first 16 bars chords to there. Then type in the chords for your 4-bar ending in the last 4 remaining bars.

Select whether you prefer 2-bar ending or whatever else, End 2-bars Early, maybe, in Song Settings.


--Mac