The Plugin is called "AQZ Netplay 0.11", for those who want to just google it.
For those who don't, I have a .zip archive containing Project 64 2.0 with the plugin pre-installed.
You can get it here (via Mediafire). Important Note: I will not supply the ROMs. Find them yourself!
That note was important, but there's a million more notes you have to take note of. But we'll talk about it later, right now it's just how this works.
Why not the actual newest version of Project 64?! I have not tested on the upgraded emulator, so I cannot say it would be desync-proof!
Why not AQZ Netplay 0.2?! Unless you are planning to play games using Mempaks or Transfer Pack, AQZ Netplay 0.2 is not necessary, and the older version has caused a lot less desync in my experience. Plus, it's easier to use!
Basic Functionment: Control Setup
This input plugin does not have its own Input Setup. Instead, it uses another plugin that is installed with your Project 64 emulator and use its control configuration. N-Rage input Plugin works really well for this, so long as you do not use a Turbo Modifier.
Basic Functionment: Booting up and hosting/joining
If your emulator is set to use AQZ Netplay 0.11, whenever you boot up a game it will ask you to verify your control setup, and then open up the Input Config window. After verifying your controls, click Save and it will bring you to a little dialog called "Connect".
The host of the Server can leave the "Host" field blank, and start a server this way. The peeps who wanna join then have to enter the hosts' IP address and click Join Server. When you are hosting or have joined a game, the button turns into the "Start Game Button", so make sure everyone is connected before you click on it!
Basic Functionment: Controlling slowdown vs. input delay
Once the game is started, the host should go to Options > Configure Netplay (Input) Plugin. There will be a small dialog that will allow you to control "lag".
This will need to be set on a level that will allow you to play without hiccups while not suffering too much input delay. The higher the value, the less hiccups, but the more input delay! The amount you need is a per-case basis. It will be lower if your friends are physically near you, but higher if there are several players from all across the world!
Specific Information and Notes
VERY IMPORTANT to consider is that games played online can potentially desync for many reasons. Desync is when what happens on one or more player's screen does not match up with what is happening on the other players' screen.
If this happen, you should first make sure that all players have the same specific dump of a ROM. Different dumps or versions of a ROM can make the emulator do slightly different things, in which case desync is sure to happen. Also, the emulator has to be the same version!
If your ROM is the same on all ends, there's also multiple other factors to consider before and while running a game. A rule of thumb is that the save file has to have the same relevant information saved onto it. If someone plays a file with all characters unlocked in Super Smash Bros., another player who has a fresh new Save File will see the other player failing to pick a locked character, for example. More specific information below.
For all N64 Mario Party Games:
