Where do i install it.. i got my multiplayer Key and followed the instructions and i still get booted from the server saying the cd key is Banned
Well, I haven't tried this myself yet (as I've not gotten around to playing NWN yet due to my hefty games backlog) but the instructions I was given by GOG support when I asked for my unique key are as follows:
1) Extract nwncdkey_<user_email>.7z archive and replace the nwncdkey.ini file in the Neverwinter Nights Diamond game folder.
2) Next install the Premium Modules Re-installer (Kingmaker Setup). The modules will now be adapted to the new CD keys.
Is this what you were told to do?