Saying it with the hard R, meaning `Ni**er` is totally not allowed and is an offence deemed punishable with a ban. This includes any form of the word that may bypass the filter, such as replacing i's with 1's or g's with 9's - The list goes on.
The mentioning of the word that is not deemed to be prohibited is the soft version, but could very easily be turned around. 'Ni**a' this particular version is allowed to be said in-game.
Insulting a players country is also not allowed, and breaks the rules falling under the discrimination Act.
@AvenTadoR would not have banned if this was a first time offence, so it means you've warranted the infraction leading to your ban.
@Mike Since this is apparently a staff complaint as well, I'll need you to review and close it. Guy isn't happy with my response on his original appeal, after he tagged half the staff team.