how to unencrypt

Could any1 teach my how to decrypt System.mrs so i can edit them. i would like to learn how to

Thanks for your time.

First of all, it's called Encrypt & Decrypt, not unencrypt.
You just need the "Code", which should be in the runnable, to encrypted the file.
You can also use brute force, it works for the most "noob" Server.

use brute force right