My first attempt was on OS X Yosemite 10.10.5. I just tried on Windows 7 running in a VirtualBox VM. While I was able to install the v.1.68-19 driver and get Windows to see the Explorer 2, I get the same error message as I do on OS X when I try to update the firmware.

Antipodes CX + Roon, 818v3, DSP 7200SEs, 218, DSP3200s