If you have any issues with the Biab Plugin you can try it in
KV Element by loading KV Element into your DAW then simply drag the Band-in-a-Box DAW VST3 Plugin.vst3 into it (you can drag a VST3 into KV Element VST2) connecting up the outs/ins. Make sure you enable EXT to sync.
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ReaTrak Biab & Plugin in Reaper
Free Biab Chord Picker Tool