Finally back with a conclusion after having life get in the way of this project. I learned how to get into the BIOS on this computer, and tried every combination of activating and de-activating the usb ports, audio options and a host of seemingly unrelated settings over the course of a few weeks. I never could get the darn thing to work. I have re-purposed this computer and was able to install the DAC on another Windows 10 machine, a Dell laptop. For reference, the problem machine is an ASUS VIVO M32CD series. It is advertised as having "SonicMaster" audio, "a combination of hardware, software and tuning to provide superior audio". I have not confirmed this with ASUS support, but I suspect there is an inherent incompatibility with their system and the BHdac/xmos driver. Computer shoppers beware if you want to use this DAC!
Bernie