Here is another way as well. If you do not want to redirect the port to your local PC, change the 127.0.0.1 under the label "Default Mappings" for an IP address on your local network.
Once you have done the mapping, please check the port has been mapped for you. GateKeeper --> Extended Networking --> Port Security.
Please let us know how you get on, and whether this was what your desired result was.