MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
OK, got the lids to show up correctly in Simplify3D by importing them into Microsoft 3D Builder and saving them as a .stl file. Then importing the saved .stl file from Microsoft 3D Builder into S3D. Thanks for that information.