HI
My model when the ‘render’ view is selected looks like the material is some watery transparent colour. I sleet object materials and dog them on to it but nothing changes it, i tried to render out it comes up as the white/grey default. I haven’t fiddled with many settings so not sure what has happened?
Can you post the file?
I have the exact same display problem with a file that has Maxwell materials applied in WinRhino - especially a car paint material created with the material wizard. It displays correctly in Windows. I can’t be sure that this is the cause - I haven’t been able to test it further (I’m home with a flu and my Windows machine is my machine at work) - but it’s a strong suspicion.
Philip
Where aren’t the Maxwell materials displaying? In Rhino for Mac or the Maxwell stand alone app Studio or Render? I wouldn’t be surprised if they don’t look right in Rhino since there’s no Maxwell plugin. In the stand alone app, I bet you’d need to send the file to the stand alone app on the Windows side and export the Maxwell studio file format… can’t recall the extension just now… sick too!
In MacRhino, in a rendered viewport (this is what I thought the OP also meant). In WinRhino it’s displaying ‘correctly’ - meaning that we don’t have this impression of the solid being inside out (flipped). It’s as if you could see trough the visible surface (it appears transparent) and are seeing the hidden surface of the solid from ‘behind’ (opaque - and black). I’m not sure I could explain this clearly enough 
I think the Maxwell material should be ignored (until we get that plug-in) and display like any other object without a material assignment (gray) - which it’s actually does - sometimes - for a brief moment…
Thanks!
Philip
Oh, I forgot… The same file (with the Maxwell materials) often refuse to display ‘ghosted’ correctly - not perhaps directly when opening a file, but after some time… It looks like ‘wireframe’, but it is ghosted - if you click somewhere between the isocurves the surface gets selected. So it is ghosted - with a 100% transparency.
One more funny (?) thing. This happens only in the top and perspective viewports. Front and right are ok.
Philip
Can you send the file into tech@mcneel.com with screenshots of what you see as well? This sounds like a render mesh issue or graphics card related which on OSX could be the OS version or the specific GPU. Send that info as well please and I can try to help more.
Sent 
Philip
I deleted all Maxwell data (in WinRhino) and now everything is displaying as it should (also) in MacRhino.
Philip
