I've seen a few other posts with similar titles, the advice/troubleshooting steps there didn't work for me.
Details:
Cura 5.6.0
Wall Ordering: Inside before Outside set
Support Distance Priority: Z overrides X/Y.
When I switch to Tree support the slice fails. I'm submitting that bug report next.
What else can I do?
CE3PRO_Drive Shaft.3mf