Roon (or my Mac?) crashing too often…

The first error message was something else, but the second one looks like it is this longstanding issue:

There is no fix for it yet, but the suggested workaround was to install Roon Server and run it as a separate process on the same Mac. It didn’t help everyone but in any case lessened the impact as at least the music doesn’t stop if the GUI crashes.

This separation of the server now is becoming the automatic default with the new update that is currently rolling out. Hopefully it will help you: