Hi,
Measures are added to the entire score, so it's not an option to add them only to one part but not the others.
However, if you don't want a staff that has only rests to show up on the display or print out, you can use the "Staff/Hide resting staves" option.
Or maybe I'm missing something? If so, please post a file and explanation for what we're shooting for
ttfn,
Sherry