Replace the keys here with the corresponding keys in your GOG owned games list.
To manually change your CD-Key, go to where your Neverwinter Nights 2 was installed and open 'nwncdkey.ini' it will looking something like this (Obviously I have changed the keys to 0's): Your multiplayer CD-Keys are stored in your owned games list, click on Neverwinter Nights 2, and they are listed under 'My serial number:' Rhiyo: You will need to change your cd-key if you are playing multiplayer either on LAN or the internet.