I'm glad to offer assistance. I don't know very much about the MAC version of BIAB but I'm aware the APT (Artist Performance Track) is also a feature to the MAC versions.
It should solve your issue but if not, come back here to the forum and we can continue to work on the problem.

Fortunately, the APT is straight forward and does all the work automatically which is a good thing. It really is as simple as Right Click on the desired track, select Track Actions, Save as a Performance Track. It creates a physical audio file and that's the best fail safe and back up possible.

BIAB 2025:RB 2025, Latest builds: Dell Optiplex 7040 Desktop; Windows-10-64 bit, Intel Core i7-6700 3.4GHz CPU and 16 GB Ram Memory.