As Charlie Fogle suggested, I reset BIAB 2020 to Factory Settings. Had to use the 2nd option for a full reset as the 1st option (partial reset) didn't work.

Selected the TTS-1 option for "Use Vst/DXi Synth", made sure the box right below for using with MIDI was unchecked.

Tried two different song files rendering to .WAV format using the upper tool row WAV button, and both worked like a charm.

So with no need to change the Audio driver, which is using my Roland SD-50 sound module for both MIDI and Audio drivers (the SD-50 is dual purpose), and since I'm not using BIAB for recording voice, I'm leaving it all alone and not messing with MIDI/Audio options (for now) and getting on with my project using the BIAB song as input into Bandlab Cakewalk for further processing and mixing!

Thank you Sir Fogle for the tip! Happy BIAB user again!

Cz...
BIAB,Bandlab Cakewalk,Kontakt, Cantabile, SampleTank4,IK BX-3, VB3, iZotope Suite, IK TRacks, Melodyne Studio
Kurzweil PC4SE, AXIOM-61key & IKiRigPro-32key boards, Roland SD-50 MIDI, Behringer 404HD, Maschine MK3,TC Helicon Voiceworks