I use RealBand but if you gotta use Biab,
with a midi style selected right click style name disable style, and RealDrums disabled in RealDrum Prefs you can move the midi Drums to that track.
You can import the track into the Melody/Soloist track then just move it to another midi track.
If you have a multichannel file import it then click the SEQ Sequencer button, go to the piano roll on the Melody/Soloist track, select the channel, right click select all notes and copy them to another midi track.

More Midi Tracks in Biab Win Mac

Someone else might have a better way.