Thanks again @theoutside
I contacted technical support already but no fix has been given so far.
Some update about this:
-> Looks like another user is experiencing this bug?
-> I just tested the new Rhino 8 WIP where the color Picker works nice.
Color Picker is working in Rhino 5/6/8 and in all other Windows Programs.
No way to appear in Rhino 7. I tried already to repair or reinstall from scratch Rhino 7 but with no success.
Maybe @dale can help at this? I suspect this happened because I had installed his ColorPicker Plugin
As I told already, this is preventing me from upgrading to v7.
Thanks!