I've got a Raspberry Pi 2 model B loaded with the latest image 18.104.22.168 non-generic. The Pi boots up fine and can ping URL's. When I open up the active printers screen I don't see the Pi listed, nor the printer it is hooked up to. I tried first with a Prusa i3 mk2, then with a Makerbot Replicator 2. Funny enough, I can see the Pi in the remote terminals section and can even SSH into it. Maybe there's a driver issue with the Pi communicating to the printer?