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.
All of the work was done in Fusion 360. Most people qualify to get it free of charge. Sorry I'm not going to release the original files at this time.
Also look into Blender 3D software. It's amazing and free. For making small adjustments to files turn on the "measureIt" add-on. This gives you live measurements on the model.