I'm sorry to hear you are encountering problems - both the default library and the google library connected to my KORG keyboard over bluetooth and worked fine. If your tablet doesn't work, it's either a problem with the bluetooth connection between the tablet and the keyboard or the type of bluetooth connection that your device supports. Be aware that in many cases, you need to pair the tablet with your device over bluetooth first, then connect to it in MobileSheetsPro. If you don't pair with the device, it may not be properly detected.
Mike
Mike