It would be nice if I could include a walking bass line between 2 chords. I'd like the first chord to sustain ringing, while the walking bass line is moving underneath it. I tried creating this using a comma followed by a slash chord, but that loses the essence of a moving bass line under a stationary ringing sustained chord. The chord is struck each time it appears in the song in BIAB.

The best I've been able to do is create the baseline by entering chromatic chords, alternating between major, minor, and dim chords, etc.