BIAB is limited to those tracks (without the sax) including just one audio track. The Thru track is for playing along live. The only way I can think of to possibly do this in BIAB is to have more than one instrument recorded on the one audio track.

What you can easily do is save the song and open it in RealBand where you have 48 tracks. Add the sax and any other tracks there.


BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.