Plutonium

You can unlock the rest with /unlockall in console.

Does the entire server window close, or does it just drop the clients as expected?

Instead of PezBots, you can try Bot Warfare, which has been updated for Plutonium T4.
https://github.com/ineedbots/t4m_bot_warfare/releases/download/v2.0.0/bwt4m200.zip
Unzip in %localappdata%\Plutonium\storage\t4\ and make a mods folder and drop it in there.

Show me screenshots of your firewall rules, and port forwarding rules.

You can check the API for yourself: https://plutonium.pw/api/servers

T4 should shove them in %localappdata%\Plutonium\storage\t4\players\demos (iirc)

Try our repair guide: https://forum.plutonium.pw/topic/6915/how-to-repair-your-iw5-installation

Yes, however it's not made by Plutonium or X Labs (IW4x), although it has a similar name. https://cod4x.me/

You can try and repair your game here, note that after repairing, if you try and launch MW3, it will crash the first time as it needs to delete a file from your game folder, but on the second launch it should work.

You can unlock the rest of the campaign with the console command /unlockall. (Note that this is separate from Multiplayer and will not modify your stats there, and vice-versa.)

Are you talking about servers, or the client?

For servers, just create a shortcut for your specific start.bat and you're done.
For clients, we do not support shortcuts, as you must go through the launcher to get updates.

Hope this clears things up.

Have you tried the port forwarding option?
Sometimes UPNP can be quite garbage, depending on your router(s).

When you port forward make sure to also open the port inside the host's Windows Firewall Guide here - Port: 28960

Going off of what Xerxes said, simply wack password qwerty where qwerty is your server password in your console prior to connecting.

Yep, has nothing to do with the client itself, you'll have to contact the specific server for inquires.

// Locked

That port forwarding rule looks good, did you add it into Windows Firewall?
https://www.tomshardware.com/news/how-to-open-firewall-ports-in-windows-10,36451.html

This does not look like what the launcher brings up, are you sure you are running plutonium.exe it should look like the following:

Launch in LAN mode, and you should be fine.

Keep in mind I'm not a project developer but from what I've gathered: a lot of Reverse Engineering (IDA) & C++ iirc.