Hmm. So in cutting off a piece of geometry for you to sample, I've encountered something very strange:

I selected a piece of the original model, deleted the rest, and did a save as. When I went back to open my original, I now have two instances of almost every face in the object. I have to delete them manually as far as I can tell, although I really hope there's a way to collapse/merge them. In fact, I just reopened the piece I trimmed out and it ALSO has two faces where there should be only one. What could possibly cause that to happen?

Here's a screen shot - the clipping you see is the faces on top of one another:



I've also attached the LWO, the 3DM, and a render of the artifacts I'm getting.