Hi, I have made a installer script which builds a custom c7 installer iso, which delivers xen 4.4 stack over minimal c7 installation. I have already tested it out c7 and c6.6 but it should work with any fedora installation also. https://github.com/gautamMalu/CentOS-xen
It uses virt7-xen-44-testing repo (http://goo.gl/b2w53S) so you will need access to internet during installation.
It uses custom anaconda so you can use it with your own ks scripts. https://github.com/gautamMalu/XenInBox
Here is link for pre-build iso https://www.dropbox.com/s/e2h2zh2mb0u629k/c7-xen.iso?dl=0
Please test it out, and provide your feedback.
Best regards, Gautam Malu