I would use RealBand for this.

The fast and easy approach (there are more sophisticated approaches):
Create the solo with the BIAB soloist.
Save the file.
Open the file with RealBand.
Delete in the soloist track what you don't want.

You will find more elegant ways to do this when your knowledge grows.


Desktop; i7-2600k, 8 GB mem., Win 10 Pro, BIAB 2017; RB 2017 - latest build
Laptop: i5-2410M, 4 GB mem, Win 10 Pro, BIAB 2017; RB 2017 - latest build