According to a trusted user, you need to disable a check box that prevents duplicate notifications in other SMS applications, like the stock Android Messaging application that emits the events that Enhanced SMS & Caller ID utilize.
So just to reiterate:
Please note: The latest versions of Go SMS, the "Disable other notifications" is in 2 places (the "Notice" - enable notifications and "Receiving" - disable other notifications). Please make sure to update both locations.