Having bb\Data\BBoutput.txt of the current tracks in Biab, that is updated each time anything is generated will give instant identical track transfer to RealBand and BBPlugin, also allowing Reaper to read and instantly load the Biab session in wma or wav or m4a or aiff.
You could have the midi data in the same file or have 2 txt files, one for audio data and one for midi data.
Having these track data txt files you could either load all tracks or selected tracks into RealBand, BBPlugin or Reaper instantaneously.