In both 2014-05-19 and 2014-05-20 I’ve noticed an issue whereby one surface of a model I am working on is invisible in perspective mode using rendered or shaded – but only sometimes. When I rotate the model and look at it from the other side of the object I see the surface. I’ll upload a video to http://www.rhino3d.com/upload to show what I’m seeing. Below are three screenshots: the first showing the invisible surface, the second showing object from the opposite view and the third showing the previous, but in ghosted mode.
You just sent an MP4 video instead of the file so all I can do is guess.
If I had they 3DM file, first I would run SelBadObjects and I would expect the polysurface to select.
If it did, I’d run ExtractBadSrf. Most likely the surface that isn’t generating a two-sided render mesh would extract.
Then go from there to fix the surface. Details for fixing bad objects are on the Wiki FAQ page.
There was a surface edge with an issue causing the render mesh to not shade correctly. I believe it was one of circular cut outs. Select the whole model>Explode>RebuildEdges>Join and it should shade nicely for you.