Organising Curves prior to OpenNesting

My aim is to nest a series of cutting paths for CNC cutting. I’m struggling to organise my curves, I’ve worked around it with list items, but this solution won’t be effective for more complex parts of the model.

I’m starting with trimmed solid as cutting paths, these have with slots for CNC and internal contours. Surely there is a better way to handle the data tree for these.

240522_OpenNest [PROBLEM].3dm (838.9 KB)
240522_OpenNest [PROBLEM].gh (49.5 KB)

Found this solution elsewhere - OpenNest fails to Nest booled Breps - #2 by kev.r