For paid resources that are not on the hub, the creator usually provides a text file with links to the dependencies. Vam used to use a file called something.var.depend.txt that lists all the dependencies. The current Vam doesn't need that, but if you get a scene or look from Patron, and they provide that file, that should have links to the dependencies. Some creators have links on their Patreon to non hub hosted files you'll need. With files that are hosted externally, you can't use the Download All button. That's just the way it is.