I had a quick look at Studio One and got it to send the BiabVst midi channels out to the instrument tracks, see pic below.
Reaper is really easy.

To generate midi only with the audio files Generate > Custom > All Pages (Midi Only)
there is no option on each track's + to generate midi only without the wav.

And here are the track channels thanks to MusicStudent
Track Channel
Bass 2
Piano 3
Melody 4
Thru 5
Guitar 6
Strings 7
Soloist 8
Drums 10

4k Pic All Tracks Full Screen

Full Screen Pic


Another way I found is with ElementVST, you simply load the Element vst3i or vst3fx
click view top right
now simply drag the Band-in-a-Box DAW VST3 Plugin.vst3 into it and the other instruments you need
connect them up
click MIDI in the list on the left and set channel from Omni to the instrument channel of the selected VST
*Make sure you have EXT on up in the top left so it receives sync.
Save that Element setup then just simply load it each session.
You can add whatever you need in Element like a midi transpose to transpose the midi signal up or down an octave.

If you want more midi just use another instance of the BiabVst.
Full Screen Pic