Event to determine user count after user disconnection

[leuko]

Hi all,
I have two questions:
1) What ist the best way to determine the user count after someone has disconnected? I tried this with the event ChangeState, but it seems that the user count is not immediately updated until another call.

2) Is there a way that my plugin or a function in my plugin is called automatically after x seconds? I think that the Minimizer plugin does something similar but I have no idea how the code works. Minimizer has no events which it is bound to and I don't understand what the "bind" command does either.