[Joel]

Mark, I've looked at the crash report you sent in, and I'm afraid there isn't much information to go off of in the report -- I would suggest quitting OmniGraffle, and manually setting aside or deleting your OmniGraffle preferences (located at ~/Library/Preferences/com.omnigroup.OmniGraffle.plist where ~ is your Home Folder) and see if that makes any difference. If it doesn't, please let me know.

Hope that helps,