Hi, 

I have a Yamaha Tyros. You can have a fake sheet style display in the score screen that shows the melody line and chords. The chords are actually chord events and can be added by some of the yamaha software and are not interpreted from other staves. If you copy the midi to PC and use sonar for example, then export as midi0 or midi1 then the chord events are lost. You end up with the melody line. This means you could not just edit a couple of notes for example. 

I will buy anything that doesn't screw up the chord events!! :) 

Does anyone have any idea please? 

- Andy