How to install mods?

[+f0r3v3r+]

A note about the Docs and why we keep telling you to reference them

I know you don't want to hear about the Documentation, but it was written to save people from having to explain the same things over again continually.
It is written fairly clearly, in my opinion. While there are people here who are willing to help with some of the technical nuances that occur with particular tasks, it is imperative that you at least make an attempt to read and understand the documentation.
Just saying you can't understand it and it is no help, is not helpful for anyone trying to help you.
I would also outright say you are probably lying and that the docs are just tl:dr for you.
That attitude is not fair to people that may earnestly want to help you. And that is why it keeps getting repeated to you.
Someone took the time to write the documentation for the purpose - so you expecting people to solve your issues at every whim is just lame, again, in my opinion.

Here is an example snippet from the Docs to explain modding

This is a method for modding without having to replace any files in your installation.
From http://assault.cubers.net/docs/mods.html

Example:

Assume you want to create a mod that provides a customized HUD-gun; here's how you would create a mod directory:

Create a "MOD" directory in the AssaultCube folder: ./mods/MyMod1/
Inside the MOD directory, place your customized HUD-gun files, using a folder scheme that matches how it would normally be placed within AssaultCube's packaging: ./mods/MyMod1/packages/models/hudguns/assaultrifle.md3
Now to make AssaultCube aware of this mod you'll need to start AssaultCube with the argument --mod="mods/MyMod1".

To start AssaultCube with the mod argument all the time, you can create your own AssaultCube launcher (this option is not available on Apple Mac OS X). Simply copy/paste the existing assaultcube.sh (Linux) or assaultcube.bat (Windows) file with a new filename. Then edit it with a notepad application.

For Windows users, add your new --mod command line option to the end of the file.
For Linux users, add your new --mod command line option into the CUBE_OPTIONS line.

Additionally...

For the sake of ease - please explain if this issue is in Windows or Linux this time, since you seem to use both at different times.
Also, if you want more specialized instructions, you might explain what it is you are trying to mod and/or mod with.

Take any help I offer with a grain of salt. If you want help, help us help you. Otherwise, feel free to continue with your current methodology of invoking assistance - but don't say we didn't try.

As for your specific issue in this thread:
I would guess that the reason you are denied the ability to write to the launcher, is that you don't have permissions on the file to write to it. Please check the properties of the file carefully for this.

To be clear, file permissions issues are not an AssaultCube problem, but an Operating System issue.