PS - I have had no troubles running CGminer (except the initial conf file setup etc) on Windows 8 and Windows Server 2012.  My additional servers use them,just my primary is still on 2008R2SP1.
Also, give Windows2Go a whirl if you want to stay on the windows route. I'm moving mine eventually to Windows 8 on Windows 2 Go sticks.  Even on USB2 it should be all fine - except for the long boot times.