It’s kind of funny that Solid Difference union-ed my geometry. Both are closed breps, and no surfaces coincide. The difference works perfectly in native Rhino though (thru BooleanDifference). Any idea what may not be working?
When you bake Breps in Rhino, their normals are automatically flipped outwards, so you won’t see the problem.
However this does not happen in Grasshopper where you can have closed Breps with normals pointing inside.
You need to craft a C# component with Brep.Flip() method