If I had one of the USB ones to poke at, I'd snoop the USB traffic and see what it's doing. Writing a driver for a USB device doesn't appear to be terribly difficult, and if it presents as a HID device, all it needs is an INF file to identify it, all the HID device drivers are built into windows. Unfortunately, as I do not have access to one for testing, nor any particular reason to want one at this time, I can't help you guys.