Thanks Michael. Indeed I think I did use Shell before, thats the nudge I needed. As a feature request (and I don't know if the 3DM file format supports this), I'd love to be able to attach comments to an object (be it curve, solid, et al). Perhaps this is scriptable but I don't know if script's methods get called when objects are written out/read in.

In comments I could document the construction of my primitives or at least describe more about its use or even requirements for, in my case printing.

Scott