Popp keypad has a few special requirements when working with ST. If you have access to RBoy Apps you can try this device handler which is designed to make it work with ST and allow you enable/disable special features like the buzzers.
You should be able to set custom actions for locking/unlocking or if you have access to rboy apps you can use LUM to program the keypad and set custom actions/notifications as well with the above device handler.