Does the Yamaha show Midi Markers ?
In RealBand you can insert Markers in the Midi file (still waiting for that request "Chords to Midi Markers").

Biab exports the chords in MusicXML as Notation Events, if you drag a musicxml file into Reaper, split it to separate tracks then open a track in the midi editor by double clicking it, down the bottom where the velocity lane is, add a Notation Events lane and you will see the chords.
You can copy the chords from the Notation Events lane to the Text Events lane, then save the track to midi and import back into Biab or do it all in Reaper.
See how you go with that, I could probably put a script together for you to copy Notation Events to Text Events in Reaper.

You could also Opt > Prefs > Chord Output > Save in Midi file
Save As Special ABC > Chords only
then http://www.pgmusic.com/forums/ubbthreads.php?ubb=showflat&Number=372872
choose the BB Chord Output to sync the lyrics (ABC Chords, clean the text up wordpad to remove the characters you don't need).
You can also get chords from the big lyric window Print > Copy to clipboard, you just need to add 1 lyric in the track to get it to copy the chords.
This will insert the chords as lyrics where the chord changes occur in the BB Chord Output track.
But hey, it should just do all this in BB/RB.

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