I used SketchUp (free) to create a simple rectangular design. Its very simple. Shapeways says it has inverted normals, and after much googling I found Blender and tried to get the file to load in it. Many hours later, I'm nowhere. I can't even get the model to show up in Blender. Attached is the .dae I extracted from Sketchup's .kmz. I hope someone can help.