[|_MeGaTroN_|]

Substitua isso:

pawn Код:

if(strfind(Nome, "[", true) == -1 || strfind(Nome, "]", true) == -1))
    {
        SendClientMessage(playerid, -1, "Seu nick nгo pode contar colchetes ( [ ] ) ou underline ( _ )");
        Kick(playerid);
    }

por isso:

pawn Код:

new Nickname[MAX_PLAYER_NAME];
GetPlayerName(playerid, Nickname[playerid], MAX_PLAYER_NAME);
if(strfind(Nickname[playerid], "[", true) != -1 || strfind(Nickname[playerid], "]", true) != -1)
{
    SendClientMessage(playerid, -1, "Seu Nick nгo deve conter Conchetes");
    Kick(playerid);
}

Editei ali encima;...