If you build the image properly, you should be able to run pretty much any Windows image in openstack. For example, I basically followed this Windows 7 in Icehouse guide to build a Windows 10 Anniversary Edition that I run on OpenStack Mitaka and Newton.

https://cloud-ninja.org/2014/05/14/ru... (Also, must set "video" to "cirrus" when creating vm in virt-manager).

Similarly, you can create Windows 7,8 even XP images.

Also, there is a link to a pre-build WIndows server 2012 in the OpenStack COmmunity App Catalog: https://apps.openstack.org/#tab=glanc...

Finally, I've found that the NoMachine software (nomachine.com) is great for connecting to the graphical Windows VM desktop.