I used to have a Tyros and I would use the BEST midi tracks with the onboard Tyros voices. I would record those parts to a wave file (after adding fx and mixdown) and then add whatever RealTracks I needed from Biab.

You can import a wave file directly into Biab to "add" the RealTrack parts to the chords that were supplied with the midi file.

I would always check the midi file chords vs the actual sheet music for a song's layout.

You can add solo's etc.

You can also do all of this within RealBand as well.

Trax