Enabling Note Entry on non-pitch stave causes crash

In the 9/23 build, and for any build in sept that I've downloaded, whenever I attempt to edit an existing percussion part (5 line drum) the program crashes instead of showing me the usual percussion stuff in the status bar. I'm using Windows 7 and there is (in addition to percussion) a vocal line, a base line, piano (two staves) , guitar line (stemless rythmn with chords) and a Sax line. There are approximately 48 measures in the piece. The score was originally created with an August build, and the percussion can still be edited correctly with that older build.