Hello,
This is rather an early heads-up as a) Windows 8.1 is still not officially out and b) The release notes specifically do not list it as supported. Anyway, on 8.1 x64 Dell Ultrasharp Color Calibration Solution doesn't detect my display. It says the USB cable is not plugged (though it is). From the logs I see it reads the serial number then it says it failed to communicate with a display with serial number 0 (???). I tried running as USB 3/USB 2, admin, compatibility mode etc. but no luck. Hope this is fixed by GA time (or if you have tips let me know :-) In the meantime I'll get a 8.0 installation restored from backup where it hopefully works...
Regards,
Alexander