Yeah, this whole thing is a bit of a mess right now - that’s why we’re working toward the cross-contaminable licenses for Rhino 6 release. I hope that will eliminate one whole category of mess.
Right now, you have to have a Rhino 5 for Mac license to get Rhino 6 for Mac WIP keys. There are a bunch of excellent ideas that we’ve floated around that prove technically challenging, and therefore haven’t been done:
a) Allow Rhino 6 for Windows licenses to run Rhino 6 for Mac
b) Allow Rhino 5 (Windows and Mac) licenses to work in the Cloud Zoo
But like I said, both are just hard, even if they’d make your life easier as a customer. <sarcasm> As much as it might look like it most days, we are not miracle workers.</sarcasm>