Great, thank you very much. It helps a lot to start.
Some times I see a blue progress bar at the bottom of the Rhino UI. This is a precalulation? For example if I moved E upward than I don’t see an updated animation. Do I need to update the calculation?
I removed all constrains and try to rebuild the whole setup. How can I get the translation of C fixed to the world space? I will be ask for two objects.
At the moment I’m a little bit confused from the connection buttons/names and what the meaning could be. In the past I used ProDesktop and I found the names and symbols was easier to understand. but maybe I need some time only. 