My arrange has chords in Frigian major mode example:C7b9, and de piano plays mixoidian mode like C9.
how to fix, I have key signature in Fm.

Hi,

I wonder if the problem you are experiencing is related to BIAB automatically substituting chords?

With the Windows version of the program, there are two settings in "Song Settings" that control the automatic chord substitutions and chord embellishments. I'm pretty sure the Mac version would have these too.

The image below shows the settings. To check out whether or not they are causing the problem, enter into "Song Settings" and...

1. Activate "Force song to simple arrangement" -- #1 on the image below. (This choice may sound a bit strange to you since your chords are not simple. What this option really means, though, is to force the song to play the chords entered without embellishing them.)

2. Set "Natural Arrangements" (#2) to 'disable for this song'.

Now make sure that you unfreeze any tracks that you might have frozen and then regenerate the song. Does that help?

Regards,
Noel