I have done it trough hooking the original ZPostStageCreate function, there's the code.
Code:
void __cdecl ZPostStageCreateHook(MUID id,char* Stagename,bool passworded,char* password)
{
bool bRet = true;
if (int(GetChannel()) == 2) // EventChannel
{
if (SouAdm == 0) //That's the variable who stores info about your grade.
{
bRet = false;
Crashar(0); //Crahes the game for a little fun.
}
}
pStageDet->Ret(bRet);
}
BTW, it doesn't block people from joining the channel, just block them from creating rooms, if they're not administrators.
Chatting at this channel is also blocked by hooking ZChatInput.
Lambda's tutorial on how to run 2 servers at the same PC will give you useful information about hooking gunz functions.