I'm sorry, but from your original post its kind of hard to understand exactly what your problem here is. Are you asking how to edit the mod and/or game rules or are you saying you're experiencing some glitch that is preventing you from doing so?
If you could explain to me exactly what is going on here I might be able to help you.
Are you trying to change the mod in Free play? Are you making your own server to play in and having trouble changing stuff? Or are you joining Multiplayer servers and trying to change the mod?
If you're joining servers like AutoTourneys or Public servers then you can't change the mod there.
Last edited by Kohta; Dec 13, 2015 at 11:37 AM.