Post: #2

I would use server timerf, set "var.timevalue" and fill it with random number. Now show dialog/or spread message.
Then again, timerf for countdown on players (i think you can clear a specific timer(this would do the .continue <number> function) and if it expires -> disconnect).

Better would be creating a dialog with some random things than this message. Taking the message with external apps and comparing is easier than comparing pixels and pictures in dialog. From time to time you'll have to change the system or create database big enough that it won't worth creating automatic external script.

E: Imho, this is not a good way to keep players playing for fun. But to piss them off.