That Script is damage don't do the job, You need to put a counter in the join to a maximum of whatever number nick enter, later all the nick who enter above that maximum of number pass to a onjoin ban list.. and ban and kick.
Example:
on @!:join:#: {
Inc -u1 %JoinFlood 1 | If (%JoinFlood >= 3) { hadd -mo Ban $address PPF? | ADD DENY $address 0 | KICK $chan $nick :PPF? }
}
And later leave your ban list do the rest of the dirty job
PD: That's an example of how is the script.. just use the the combination of a Ban List of whatever you has.
Most servers have a limit for amount of used commands within a timeframe for like mode / kicks / privmsg / nickchanges and more so to set an unlimited amount of kicks wont work as u most likely will get disconnected