salam263

Ah, so I'm guessing you're not familiar with archives.

Here's how it works: When someone wants to share files, like a mod, but need to make it smaller, they turn the files into an archive. An archive is a bunch of files compressed together and made smaller than it actually is. The most common types of archives are .zip, .rar, and .7zip, but there are others.

To return the files to normal, all you need is some sort of archiving program. I recommend you use WinRar. It's suppose to be a program you have to pay for, but you can download the trial and it won't expire (the developers are too lazy). It should be pretty easy to use.

After that, you should be able to install the mod.