For those of you experiencing this crash:
RH-55141 Crash after New Document creation on macOS Catalina
there is a fix in the latest Service Release Candidate for 6.19.
Please let us know if you are experiencing the same crash after updating to that Release Candidate (once you update, your version number should say: 6.19.19283.04382 or later).
Of course, if you are experiencing different crashes on macOS Catalina, let us know - but preferably in a new topic.
Thanks again to all who helped track this down!