Yes, games and gaming systems in general usually needs multiple ports.
For example, the 360 need 4.
There is the option of opening all ports to a selected IP,
However, this is unadvised if you can simply make all the ports.
The UDP ports all need to be open is basically what it means.
Your ports have a maximum quantity, so make the starting 1 and the ending the maximum.
I have a remade version of this guide, since Dawei "borrowed" it from me (

) and will post it if you guys so desire.
It has been somewhat simplified and expanded on, but the basic information is still the same.