'Empty output' is an return message from our MeshMedic. It means that when Meshmedic tried to repair your model it ended up with an empty output as a model. In this case (SS101) you have so many inverted normals (if not all of them) and shells in your model that when Meshmedic tried to repair those inverted normals the shells didn't seem to belong to eachother and got removed. It seemed to have done that to all shells, leaving it with an empty output.
You should remove all inverted normals from your design.