The NS4 (and most NWN servers) don't like CD Key changes. But that's what needs to happen.
I know that you can log into your GOG account and that your NWN diamond edition will have a set of 'multiplayer keys' available somewhere. You need those, because the default CD keys are not valid for multiplayer. Once you get those CD keys sorted correctly, use the 'shortcut' method that I linked previously. This will remove the unnecessary steps of the NWN game and the multiplayer menu and server list and crap. Use the info as shown on the wiki, not a numeric IP address.
Once you have those 2 things sorted, then try to connect. The username is the only part that matters really, passwords were disabled a long time ago when Bioware stopped hosting the master server. So pick a unique account name and a (at least) 1 letter password.
Once that's done, you should be able to hit connect, wait like 10 seconds until the master server message pops up, click ok, and you can create a new character. You may need to wait a couple minutes (up to 30?) if you have changed the CD keys recently.
There may also be some port issues, try this:
viewtopic.php?f=147&t=1004054&p=1046415&hilit=client+port#p1046415Also to remove the master server timeout/waiting, try this:
viewtopic.php?f=17&t=1003167&p=1037434&hilit=master+server+hosts+file#p1037434You can search the forums here using the search at the top right of the page. You can find things like this:
viewtopic.php?f=20&t=1003731