You can use the Edit Player Info command (Setup menu) to change the way staves are spaced. This is the only aspect of your page layout that is the same for parts and scores. The piano setting in the clef pop-up menu gives the player two staves, with bass and treble clefs. All the other choices result in a single staff for the player. The ledger line settings in the window control how much space is needed around this player's staff or staves, expressed as a number of ledger lines (equal to the space between two staff lines). When working with a two-staff player (“Piano” clef), the setting called ledger lines between controls how much space appears between the player's two staves.