I haven't tested whether follow me works or whether this works on any MD's other than the one on my core and I'm not sure if there are better ways to do this or if some of this isn't required, but here is how I got my PDA working as an orbiter:
Pair the devices by using the following:
run: hidd --connect <MAC Address of PDA BT>
Enable Personal Area Network on the CORE:
PAND_OPTIONS="--listen --role NAP"
Set a static IP network for the core to speak to the PDA:
add to /etc/network/interfaces:
iface bnep0 inet static
Reboot the Core
Set the IP of the PDA to be 192.168.81.2
Then on the PDA use the BT manager to connect to a network and find the core and connect to it.
In the orbiter set the IP as 192.168.80.1 (assuming you use the default IP) and put in the device ID established by the core.