Opening Specific Ports?

[#1]

Is it possible to open a set of specific ports? 

From the options when connected to the router admin page I am able able to select specific games and applications but not the specific port which is needed for a game server I am running? 

Does anyone know to do this? 

Moderator's note by Adie (Dvorak) All caps title removed as per Forum rules

[#2]

I assume you're using the PlusNet HubOne?

I don't have access to one at the moment, but have a read of this thread which may help:

https://community.plus.net/t5/My-Router/Hub-One-Port-Forwarding/td-p/1403995

Especially this post:

If you go into Advanced Settings > Firewall > Port Forwarding , you should be able to input any internal IP you want to forward to. If you want to add a custom port, i.e one not in the drop down list, click the Manage Games & Applications button, at the bottom of the same screen.

[#3]

Yeah i am using that hub, should've stated in the original post. Cheers for the link