Excellent. Thanks again, and thanks for making me do it myself.

Thanks. I didn't know I had a Ruby console (using Make 2017), but I'll look. Didn't use perspective camera because I'm working in 2D/parallel all the time. Very likely duplicate IDs - I have never been able to find, use, or delete a group after creating one. You may infer I'm a rank beginner...

I've had this problem in the past when I had too many Dimension items, but this one has none. If anyone can tell me how to locate the reason for the failure, I'd appreciate it.
Sheet4c.skp