The problems I have had with expired certs have all shown up when I
tried to use the App Signing Tool. I redid my certs this time because I
had one that was expired, but after that I had no problem signing the
app and submitting the app. It is a good idea though, and unless someone
has some experience with it crashing like this then I will probably just
rebuild it in the portal, resign it, and resubmit a new version to the
appstore.