Yes, you can send the midi channels from the BB Plugin track to other tracks/channels with different virtual instruments on.
You can have another BB Plugin on another track sending to more virtual instruments.
You can have another BB Plugin on another track sending to the one virtual instrument and by soloing each track in the BB Plugin until you find one that fits best.
You should also have MultiRiff Midi soon that can just generated up 7 tracks of the same instrument for all bars or just the selected bars.
There will be an option soon to generate just the midi only without generating a rendered wav file of it as well.
Always look in the Win Plugin forum also,
this is an older version of the BB Plugin, to get the BB Plugin track to playback in sync to the DAW you double click the little drag icon after the track name. The next version of the plugin you will just select the track name with one click and you will have a sync to host button. Video: Playback Audio/MIDI Tracks from Plugin