you're just going to have to search for a low GB requirement hub on that app now.
To download in it, once you're in a hub, you just search another members files & grab what you like. Some won't let you, but that's how it is.
I used to use this app when they first started (when only 5 hubs online lol), but over the past year this thing has gone downhill in my opinion.
It is alright once you find a group you like, but they are just getting to bloated with themselves now.
Good luck