You can select a range for both the melodist and soloist can select a range to generate. So yes this is possible and fairly easy.

<Shift><F5> (Select Melodist)
On the right side of the screen near the top select Part of a song
Now fillin in the range you want to generate.

Select chords and melody options. (you can generated one, other or both.

pick any other setup options you want and click ok.

BIAB will regenerated the bars you selected.

You can do similar for solo by selecting a custom range.

HTH


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