I agree with a lot link has said, if you TK during nade or after round, your taking a risk, so I just only TK people I know that won't slay me. As for the nade round, sometimes its harder because you are just throwing grenades at will and blindly but with that said, just go to the other time and knife them.
Also camping isn't against the rules unless it's excessive, I think this is something that a select group of admins just need to learn to live with.(unless we decide on a new rule).
Of course other rules that need to be said, no leaving and re-joining to gain levels that might be the only GG related rule I think of that isn't a blanket rule for all the servers.