How to get there
Choose Plug-ins > Scoring and
Arranging > Piano Reduction.
What it does
The Piano Reduction plug-in helps you to
easily condense a number of staves into a piano grand staff. The piano
grand staff will be added to the bottom of the staff system.
Select the staves in your document to be included from this list. CTRL-click
to select multiple staves.
Point. Set the split point for the piano staff.
· Cancel. Click OK to make the selected changes. Click Cancel to
dismiss the dialog box without making any changes.