I’m not entirely sure about the engine-specific files, but you will need to host the files yourself and provide FAB with the links to them. For instance, I store all my files on Google Drive and simply share the specific file links, which works perfectly. I assume that even if you’re not creating a project file, you’ll still need to host your files somewhere and provide access links. You can use any file hosting service; I prefer Google Drive since I already utilize it for various purposes. However, options like Microsoft OneDrive or any other file hosting service would work just as well.