It seems this is more of a Windows 10 problem than an apple problem. Was able to get the firmware updater to work, but there's no USB MIDI functionality afterward. USB connectivity appears intact to Windows 10, just not MIDI. And the Neutron app doesn't think it's connected.
Yeah, this is irritating. I've reinstalled drivers with Zadig, etc at least 10 times now and nothing changes, USB MIDI still doesn't work. It bothers me that this thread is over a couple months old, and nobody from Behringer has piped in with a definitive response for what driver will work with Windows 10 (hint: WinUSB (v6.1.7600.16385)) isn't the answer), where to get it, and how to get it installed. I think the Neutron is an amazing little box and I love it, but this is stupid. I plug in my Moog Grandmother, and it just works. No screwing around, no downloading utilities and going through arcane boot procedures, no nothing. It just works. I think Behringer can up its game here a bit. Say SOMETHING, if there's a bug in the firmware ok just say so, and give an idea when it'll be fixed... but don't leave your customers wasting their time please.