Hi Ian, I tried that, but still no good.
I had opened a ticket with C1/P1 on this and did hear back. It's a known bug since version 20.0.2. Seems to effect some windows 10 machine and not others. P1 has known about it since Jan 2020, so I guess that they will eventually fix it.
It's strange, I have 2 windows 10 machines, both home built Asus boxes, 1 is 4 years old, and my main machine for processing, and it fails to work on that one. The newer machine the plugin works.
P1 stated it has something to do with code changes they made to 20.0.2 and how extensions are handled.
Paul C