Yeah I've been all over that page.
I have had it installed as it was carried over during the upgrading process, but it wasn't recognised inside of Sonar. So even if I managed to get it installed again I doubt it would work.
I heard back from Boss today who said:
"The Windows 10 drivers for the BR-800 are currently being reviewed by Microsoft as we speak.
A release is due any day now but please keep an eye out on the official downloads page below where the driver will first be released"
Hopefully that will be the case because I badly need to start on things.