Alain.....I have recently been discussing just this point with the Yamaha Factory demonstrator staff. Select a style suitable for the song you wish to perform with right hand voice..s. Save into a Reg Bank 1 with name of song. Duplicate this into Banks 2. 3. & 4 or up to bank 8 if you wish. Each with a different right hand voice to suit different parts of the song. You can even mute some of the style backings in Bank 1 and add them back by un-muting as you save into Banks 2. 3.& 4. I set my right hand sustain pedal to trigger the Bank Registrations and just press it as I move though the song. You have over 600 Registrations, so plenty of room for a load of songs settings. You could select any suitable ones from the Music Data Base and convert to your liking and then save into the Registration Banks.

Graham UK