Installing crown moldings in 3 dimensions

[Plaincollar]

Hello
I see that the question has been raised in previous threads. However, I haven't seen the solution to this.

I have built a room with two walls under a sloped roof (see image). The angle of the walls is 90° and the roof slope is 30°. The moldings rest at the bottom against the wall and create a shadow upwards.
When the cove moldings are to meet in the corner where it deviates in three directions, I can't get it to work. Is there even a solution to this? There is quite a bit of discrepancy at the bottom of the descending one.
(The moldings in the image are oversized but correct in the proportions).

Anyone, who isn't like me; wage slave, who has an idea on how to solve this?

 

[Joak]

The list that should be above the door needs to be cut at the back. That way, it will be like a regular outer corner.

 

[Kurtivan]

Here you can read and learn a bit about practically mitering ceiling moldings: http://hvilaro.blogspot.com/2008/07/gering-taklist.html

 

[Plaincollar]

Here is some reading and learning about practically mitering ceiling moldings:
[link]

A good link and if he is right, such moldings in such angles should not be installed by amateurs. Physically impossible to fit such a corner without modifying the molding.

 

[Dublin]

I recently renovated the bedrooms in the countryside with sloping ceilings, and I actually thought it looked best without moldings. I painted the ceilings and then wallpapered the walls, and with the help of a long steel ruler, it was easy to cut the wallpaper right at the transition between wall/sloping ceiling.