Hi @hanscad,
You just linked this old topic from Named CPlanes disfunctional? - #7 by hanscad so I took a look.
I noticed that your views are set to cplane top, cplane front etc. which made me wonder whether you had been setting views in between trying to work with your three named cplanes. If so, you may have been changing the CPlane each time you set the view. If you have ‘Named views set CPlane’ turned on, try turning it off and see if you get more expected behaviour.
I found, like Pascal a year back, that your Named CPlanes behaved consistently. I had that setting turned off. When I turned it on and changed views things became much harder to follow (but were happening as expected once you understand the effect of that setting).
HTH
Jeremy