What type of connection are you using into the Balance 30? An easy way to test specific ports would be to enable WAN pings and specify the port your trying to forward. If you can’t hit it from remotely then the provider is liking using a private Nat’ed address. You could verify that by going to the dashboard and clicking on the WAN details to verify the IP, then go out to ipchicken.com and see if the IP’s match. If they don’t, that’s going to be the first part of your problem.
Off the top of my head if your connection type is AT&T Uverse, AT&T 3G/4G, Verizon 3G/4G, Virgin Mobile your going to end up with a Nat’ed internal address.