First you'll want to download the script file here. (Right click and 'Save As..') Place it in a directory that you'll remember and won't be tempted to move it from, ideally your mIRC folder.
If you want to take advantage of the EZ toolbar button, you'll need to save this: 
in your mIRC folder.
Once that is done, go into mIRC and click on the green "/a" button in the toolbar, which will take you to the script editor.
Next, click on the "Remote" tab.
Now before we continue, if you have a previous version of the NPC script you'll need to unload it before loading the new one. Otherwise you can skip this step.
Now, first you need to find the current script under the 'View' menu. It will likely be called NPC_Client.ini, or NPC_Basic_Server_Pack.ini. Select it so that it has a check mark next to it in the 'View' menu. Once you've done that, go to the 'File' menu and select 'Unload'.
Then, go to the "File" menu, and select "Load", or just press Ctrl + L.
Finally, navagate to the folder you save the client file to, select it, and either select 'open' or double click on it.
And now you should have a functioning NPC client script!
To learn the commands for the script, simply enter "/npc help" and the help window will open, detailing the various commands and features of the script. It will explain the commands, as well as give you some up-to-date information reguarding bug patches and possibly new features.
I highly suggest you read the help. There are far too many features for me to explain to everyone now, so if I bite your head off when you ask, you'll know why. ^^;
Just so you know, the script will now work when the main server isn't online, but there will be a delay of roughly 30-40 seconds before it will initialize its internal basic server. This is normal. The basic server will open a second server window, so this is also normal. The main server contains much more detailed error checking than the internal server, and the script will try to use it whenever possible. The delay might be longer due to increased traffic, but only in relation to the delay between the IRC server and the NPC server.
If you have any other questions, I will probably be in #npc or you can leave a memo to my nickname, Tumbleweed, and I will try to get back to you.
