Per Jean Fred:
I gave a try at uploading an Stl on the Beta cluster (a conversion from the Obj on Sketchfab) :)
(I had to resort to the old uploader as the UploadWizard kept failing with a "Cannot save temporary state" or smth like that)
(@MarkTraceur reproduced with DavidStatue.stl and confirmed the actual message "Internal error: Server failed to store temporary file.")