Waffle Invalid surface

Hi everyone, I would like to ask for guidance regarding a project. I’m trying to make a waffle
assembly through CNC but an “invalid surface” error always goes out. I can’t also seem to bake it.

Thank you!

01|690x243 Base Geometry 091519b.gh (25.0 KB) Query 091519.3dm (2.3 MB)


You must use curves in C input

And what you want is not clear ; why you want split the surfaces where they don’t need to split? z=0