Welcome to the forum, Greg. It would be helpful if you could please do Help > Create Diagnostic Report and attach the resulting zip file, which will be created on your desktop. This will allow us to take a look at the logs and see what’s happening.
I have been working with a user recently who has been experiencing crashes when editing e.g. the altered bass note of a chord like Eb/Bb. When he opens the second chord symbol editor, to edit the Bb altered bass note, Dorico sometimes crashes when leaving that second editing dialog. If this describes the problem you’re experiencing, the good news is that I believe we have a fix for this problem, and it will be included in the next update.