In order to remove the BlueDUN screen-lock, open your device, navigate to Settings > Common Settings > Screen Lock and select another screen-lock method. Alternatively, since you no longer need BlueDUN, you can uninstall the software from your Android device. Go to Settings > All Settings > Apps/Applications, select the BlueDUN program from the list and tap Uninstall. You can use mirko.solazzi@gmail.com
email address to get in touch with the official developer for further information.