Thanks for taking the time to look at my script Seghier. I understand your suggestion, but it fails in the case of a filleted polygon because when a non-zero fillet is specified the PCen component changes the polygon from a Polyline to a Curve, and this causes PCen to fail. I guess this is another of the little quirks (features?) hidden inside GH.
Your suggestion works fine with a zero fillet, but fails with any positive value because of this. The overall scaling seems to work the same in either case however.
PS: I plan on using this approach to create a “waffle” bottom on things I 3D print. What I’ll do is set up an array of (probably) scaled squares and use SDiff to subtract them from the solid flat bottom of my object to be printed.
Thanks again for your attention to this. I wish I knew how the GH experts here figure out stuff like this.