"Assertion Failed" error message

I keep getting an error dialog, “Assertion Failed …” (see attached) and then CB6 closes.

What’s causing this and how do I fix it? (I already deleted preferences.)
CB6 error.JPG

Bump - I’m still getting this message immediately followed by automatic shutdown (i.e., losing everything that wasn’t saved).

Anybody seen this message or know what it means?

Google search SEModule_base.ccp and you might find something that relates to your system. KVR Atomic maybe? Only you can know - it’s very likely to be a plugin you use.