It's working via a D-Link Bluetooth adapter, the one Apple sells in its own stores. Now I just need to convince PowerPoint to go to the previous slide when the "back" button is pressed rather than trying to right-click in mouse mode or do nothing in presentation mode. Any tips there appreciated, though I have hope now that the system actually sees it at all.
Currently using it as a mouse on my light blanket (sitting on my bed). Very nice so far.