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.
you can also go to your queue and see the error for you job. Click on "see details". In there you will get the url that is getting an authentication error (403) and can copy that (it will look like https://www.thingiverse.com/download:4095594). Paste that into a browser and when asked what to do with the file simply "Open With" and use OpenScad. This of course makes me wonder why I do not get a 403 when opening the file and they do but that is a different story :-(
I have attached an rtf with screenshots just in case.