Reversed Faces

[cadmastr]

I hope I am posting this in the right area.

Question:

Does importing an AutoCAD model into SketchUp deal with faces in a different way than models created in SketchUp? Here is what I have done:

I imported an AutoCAD model into SketchUp and the entire model had the color (blue) that reversed faces normally take on (and I did confirm that the faces were indeed reversed). However, I was able to add materials to this model (without reversing the faces) and then render it in Kerkythea and it turned out very nice.

When you try the same scenario with a SketchUp-created model, it doesn't work. I made a small model in SketchUp, reversed one of the faces, and then added a material. I then brought it into Kerkythea and tried to render it. The face that was reversed would not render; it merely appeared "white" in the rendered output.

Therefore, my question is, how come an AutoCAD model that comes in with all faces reversed, can have materials applied and be rendered successfully, whereas the same scenario with a SketchUp model does not fly?

Does SketchUp deal with non-SketchUp imported geometry in a different way? This is blowing my mind.