I have tried numbering each individual face, to see if maybe i could select that part from a list, but the list seems quite messy, and I’m not quite sure i’m doing the right thing. see attached:
You didn’t internalize your starting curves, so your .gh definition is not building any geometry.
Also, for who, like me, don’t have your plugins (ex: “MeshEdit components”), can you internalize also directly the mesh itself?