What is the "cloud resource" so that I can select and drag it? I'm on a Mac: by "KeyShot library's relevant folder" do you mean Library/Application Support/KeyShot 6? Should I have a folder in there called "KeyShot Cloud" or something similar for this to work?
The 'Cloud Source' is a thumbnail you see in the Cloud Library in your web browser. Drag the material from the web browser to your KeyShot scene and it should then pop up a dialog for you to enter your username and password. Then you should be able to drag and drop whatever materials you want from the Cloud Library.
If you just drag and drop directly to your scenes preview screen, you might see an error saying the download has failed, however the materials will show up under Downloads in you KS Materials Library and you can then assign them as required.
Martin