I have 25 of these routers installed behind various providers and transport (DSL, Cable, UVerse).
At sites where I have static IP, I can't reach any service inside, and in fact can't even reach the router for Remote Management.
At all times the users indoes can do whtever they like, the have Internet access.
At sites where we draw a dynamic IP or use PPPoE, I can reach services and manage the router until a known issue stops the inbound traffic.
I'm about to attempt to return these devices, but would like to know if anyone else has ran into this and how you solved it.