First of all, if you have entered notes into the guitar track, make sure you have frozen your arrangement, otherwise, it's going to get regenerated and you'll lose your edits.

Assuming you have frozen your guitar and bass tracks (so they don't get regenerated - which means you need to make sure your chord arrangement is exactly how you want it), then you can use the piano roll screen to highlight the notes you want to copy from the guitar track, the click on the bass track, highlight the same are, and right click and select "Paste - Replace". You may have to do this a bar or two at a time.

It's not really how BIAB works - the guitar, bass, piano, strings, and drum tracks are designed to be regenerated each time you play the song, so that you get a slightly different arrangement each time.

You would probably be better off doing this in RealBand, where you have more control over each track.

John

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