FYI, at my first Rhino 6 WIP installation (rhino_en-us_6.0.17116.06371.exe), I get the following problem:
Thanks, this is logged as https://mcneel.myjetbrains.com/youtrack/issue/RH-39148
I already logged one yesterday https://mcneel.myjetbrains.com/youtrack/issue/RH-39143