Hi Max & Pilou - re: Crash - I investigated the crash and it appears to be a bug in boolean union, where under some complex arrangement of curves it is possible for there to get a face (curve booleans internally happen on a planar face as part of their processing) that has no loops on it which is a degenerate condition and then other code that harvests the edge curves crashes when it hits that.

I'll be able to fix the crash by just skipping over this degenerate face with no loops rather than trying to access the loops on it, but that fix won't be available until the next public release of MoI and I currently don't know when that will be.

At the moment Pilou, I'd suggest not using the script on things that will yield chaotic results like you are doing here by trying to apply it twice in succession onto the previous results of it.

- Michael