Is there a way to disable the user to open multiple process of the game ?
force to use login system generate unique ID for each run + user ID combo, store fingerprint online and call quit on most before recent login session if it does not matches last fingerprint and it is still running ( need to do online check periodically tho) If you want to do it locally then something in this terms might help you: http://stackoverflow.com/questions/171213/how-to-block-running-two-instances-of-the-same-program