I agree, the VID/PID 2A03/0043 changes when you go to the DFU mode and I also loaded the .org firmware. At the first of the thread they were both trying to get drivers for the Atmega16u2 and the only time you should even see the 16u2 is when you are in DFU mode as far as I know.
Anyway, this has been driving me crazy as I have followed the thread and I tried to come up with something else to check.