Face normals facing the wrong direction will show up red in Netfabb basic also. Upload your object/stl file here so folks here can get a better look, possibly diagnose the problem.
Ignore the comments about the normals. I had a confusion attack. You have two holes, the inner hemispheres upper edge and the outer surfaces upper edge. Netfab will just close the outer cups edge when you try to repair it,leaving 2 shells. I bet you will wind up having to perform a boolean operartion, or manually connect verts, and fill holes
Last edited: Nov 29, 2012