RaidMax This was the solution! Thanks!

The server will launch when the game is running, however the server will not show up in the list. I guess this has something to do with the server and client being authenticated as 1. I'm not sure but I hope they will fix this soon, as it makes self hosting almost impossible.

I'm had the same issue, plutonium.exe was not placed in the right directory.

Edit: I was running under wine (linux) and after a couple of hours of troubleshooting I fixed it by using wine cmd to run the bat file of the server.

JezuzLizard sure! I'll see what I can do, I sent you a DM.

JezuzLizard Thanks for you contibutions! I'll update it soon.

Link: https://github.com/niek265/BO2-No-Box-Limits

BO2-No-Box-Limits

This modification disables map specific and game specific weapon limits.
There are a couple of versions I made so you can pick witch one fits best.

Installation

Compile one of the files as _zm_magicbox.gsc and place it in \t6r\data\maps\mp\zombies.

1. double_weapons.gsc

Disables the check for already having a weapon that is in the box.
This means you can get the Ray Gun out of the box when you already have it, doing so will refill its ammo.
Having the PAP'ed version of a weapon counts as another weapon, so you can have the Ray Gun & the PAP'ed Ray Gun.

2. no_limits.gsc

Only disables weapon checks for wonder weapons, so everyone can have a Blundergat and it is not capped to 1 per game.
This also means you can have a Ray Gun & Ray Gun MK2 at the same time.

3. double_weapons-no_limits.gsc

Combines the 2 tweaks listed above. (Recommended)

4. everything.gsc

Disables all box checks, this means non box weapons (such as some wall weapons) will be placed in the box. (Not recommended)

Credits

This repository from JezuzLizard with compilable GSC files.
https://github.com/JezuzLizard/Recompilable-gscs-for-BO2-zombies-and-multiplayer

I'm getting a fatal error with this mod installed,

This is a bit weird considering the override has nothing to do with the tank as far as I can see.