If Biab can write the current tracks audio/midi data C:bb\Data\BBoutput.txt
then the Plugin or RealBand can import selected track/s.
There's no reason also why it can read frozen SGU and import all or individual track choice.
In the Plugin you can do it by right click track that give a choice of one of the available BB tracks or a button to give a choice of what tracks to import.

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Import-Current-Biab-Tracks.png (315.67 KB, 23 downloads)