Here's another way to get midi sound from the BIabVst:
You can chain VSTSynthFont after the BiabVst if you are only using midi tracks or you can create a midi send to VSTSynthFont.
The new VSTSynthFont will allow vst instruments on the midi channels as well as soundfonts.
If you just solo the midi track in the BiabVst you will see what channel it is outputting on in VSTSynthFont then set it to that instrument.
You can also use something like BassMidi to load any soundfont into.

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BiabVst-Midi-Out-VSTSynthFont.png (191.5 KB, 17 downloads)