Hi uncle.tim and NUC owners,
Intel released a document related to USB3.0 compatibility with Windows® 7.
The file is Windows 7* USB 3.0 Creator Utility
The file is available at downloadcenter, filter by the NUC model then, filter by documentation.
Please do not tell people to use that utility until Intel updates it and it works correctly. The document that the OP shared is quite helpful, although not entirely accurate. I have answered this question a number of times and outlined exactly what needs to be done. The required steps can be found in this thread:
I don't know why you are saying it does not work. Using the Intel USB tool, I have made a number of flash drives with Windows 7 & USB 3.0 drivers and they worked just fine. One thing I did notice is when you boot into the Windows 7 account setup portion for the first time, you may have to wait about 10 -30 seconds for the USB keyboard and mouse to appear but it eventually does.
One thing I have noticed is the USB tool is a little picky about what flash drives it works with. You may have to try a couple of different brands to get it to work.