The example file is attached on here (http://filesocial.com/1d4sbye).
When the file is opened, go to
File -> Page Setup...You can find another staff hidden.
<Image Link>Set the channel of three staves. They must be same.
<Image Link>Pedal (sus) is a sort of Controller, so if you set the channels same, the piano sound will be pedal-ed.
Sesirine.