System.Drawing.Color is essentially a Windows thing and there are a few things that have been translated over to Mac, but not all. This may be one of those not yet available. Let me look a bit…
Yeah, looks like rs.GetColor is good and broken on the Mac. I’m not sure if it was working before or not, I don’t see a current bugtrack item for this, so I’ll add it.
Thanks guys for reporting this. This is entirely fixable and Mitch you are correct that this is an issue with System.Drawing. I may not get this fixed for the initial release of Mac Rhino, but will definitely try.