Hi Dale,
One thing that may explain the change you're seeing is if you've added other staves to the piece which contain notes in those first two staves. The collapse resting staves command is only valid if ALL staves for a part have resting measures.
If the above does not seem to be the case, please either post a copy of the file here on the forum, or send us a copy of the file and a brief explanation of how you created the file to
support@notation.com
ttfn,
Sherry