This posting is older than 6 months and can contain outdated information.
The Harmony Hub can simulate a number of different Bluetooth devices, but always uses the same, unique Bluetooth Device Address when doing so.
In order to achieve faster connects, OS X caches device information, including the device name and HID descriptor (which describes it as f.ex. a keyboard, joystick or media remote respectively) for every device using the device's Bluetooth Device Address.
Caching this information is critical to support many input devices, especially keyboards, to enable disconnects and fast reconnects to conserve battery life.
If the same device, however, connects in multiple different roles, the cached information often won't match what the device currently want to represent.
So if for example, the Hub connects to the Mac as a keyboard, OS X will cache that information. If the Hub then wants to pose as a PS3 remote, it'll disconnect and connect again. OS X, however, may still be using the cached information, interpreting the information coming over Bluetooth as keyboard, not remote control input.
That's why you currently can't use a Harmony Hub in different roles with the same OS X system.
This is not really a limitation of Remote Buddy, though, but rather a consequence of how Bluetooth works in OS X.
