I was able to confirm the Descriptor modification with my other two laptops.
Dell XPS Windows 7 SP1 64-bit and Sony Vaio FW590 Windows 7 SP1 64-bit both installed the ArduinoDue.inf driver correctly now for the Native USB port. I also tested the KeyboardAndMouseController sketch and it works fine.
This modification is just a kludge at the moment. We need to figure out the proper code fix for this issue. Anyone else versed in USB stuff?