For your chosen application to make a connection with your elf you will need to know the name that was assigned to your elf.  After pairing your elf with your Mac, this is easy to find.

1.  Under System preferences > Bluetooth devices you will see an entry for your Bad Elf

2.  After selecting your elf, select the Settings Icon beneath the list of Bluetooth devices paired to your Mac.  You will see the following pop up menu appear at the bottom of that window select Edit Serial Ports....

3. You will see the following screen and the name assigned this connection will be listed beside Path: at the bottom.  Note this and it will be used in your chosen application to make the connection with your elf.