Port forwarding on CC is quite STRAIGHT FORWARD..

http://www.clarkconnect.com/wiki/inde...

What do you have in front of the CC box.. another router? What is the model number of the device that connects your CC box to the internet? I would guess it is a NAT router which would be why port forwarding or UPnP would not be working on the CC machine.

Please layout your network, with model number of devices and what version of CC your using - an I am sure someone can walk you thru how to accomplish the simple port forward that is required for your sling to work from the outside.