Hi Karsten and thanks.

I followed your instructions and everything works correctly with new const values.
As said by you, Loft with cap ends ON causes a Moi crash.

Only one thing does not convince me.

Why the resulting object is made by two elements ?
One, the cluttered, which is a joined surface, and the other one, a single surface sharp and clean.

You can see in this brief video the two unjoined surfaces

http://take.ms/W1efF

And here's the .3dm file

http://take.ms/qDenH

Best,

- Marco (mkdm)