Shell refuse create hollow object

Hey @JakubUrban! The shell tool prefers simpler shapes, applying the tool on complex polysurfaces may not result in a solid body - which I think is the problem in this case.
The crash also should be strictly connected to the complexity of the model, Parasolid tries to solve the issue then it runs out of RAM.

There was a similar thread at the beginning of the year, let me share it with you: