The Yaw as you illustrate works today. It's weird because I tried that mouse method and I couldn't get a yaw. Now it works great. It's probably me.

I have another problem.
I can't get the Union to work. There are 4 parts to this model, L&R wings and two bodies. I can't get them to Union. The program acts like it performing the calcs and I can select the objects ok, it calculates, but when I get control again, the parts remain separate. Any idea? I try it just two at a time, and all 4 at a time. No joy.
Thanks,
Dave