bogden wrote:

Your filler has to go on the wall not the ceiling, then when you run the
rake, the profile will match on your plumb cut. You already know you're
trying to use a crown made for a 90 degree angle to try to use for something
other than 90. Not a lot of choices without filler on the wall or having
custom crown made for the degree your cathedral slopes.

I take it you mean canting the level run upward, so the rake sees
it at a right angle. Interesting, I hadn't thought of that. But
even with the relatively low pitch roof - 3½ on 12 - I don't see
that looking good, on first consideration. Have you ever done
this, and how did it turn out?

The custom rake crown is the ideal solution, but it's not going
to happen.

p.