Hi Paul, give the attached version a try. You were 99% of the way there, just a couple of quirks at the end - the input to the boolean must be an ObjectList, not an individual object.

Also, another quirk is that the objects used in the boolean have to be added to the geometry database first so they get a unique ID assigned to them.

These are things that I can tune up later, like it would be a convenient thing if a factory could take either an object list or an actual single object interchangably, and the IDs could be assigned automatically in this situation.

This stuff hasn't been quite refined for complete convenience like this yet.

But it seems like the overall "factory" architecture is working out really well, it basically allows you to automate the actual guts behind every regular command.

- Michael