Hi Michael,

thanks for your reply!

The window frame you did is what I was looking for.
Maybe I will try to include the face behind as well.

I know, that I cannot fillet edges, where edges come extremely together like
in some corners. But I tried only some edges with enough space and that also did not work.

Can you try to bevel f.e. just the roof-top-edge.
A small bevel amount would be enough (just to break the hard edges a bit)
and maybe send me your file back?

thanks very much
Mike