Therion gives me an error for a situation that seems to be ok, maybe I'm missing something or I may have found a bug.

In the first image the inner wall is defined "out" and the yellow tick facing outward and this works fine.

In the second image I added another inner wall which is also defined "out" and with the yellow tick facing outward and I get the error "multiple scrap outer outlines not supported yet".

As far as I understand there shouldn't be an error because both inner walls are defined correctly.