WHy this script not start working when player join? always need to restart script.

[Viudes]

local connectedPlayers = getElementsByType ( "player" )
for i, aPlayer in ipairs(connectedPlayers) do
	bindKey ( aPlayer, "x", "down",SuperStop)
end

WHy this script not start working when player join? always need to restart script. 

[Addlibs]

Your code only binds the key to every connected player at the time of starting the script. You also need to add the following event handler:

addEventHandler("onPlayerJoin", root, 
  function()
    bindKey(source, "x", "down", SuperStop)
  end
)