Sorry to correct you buddy, but Windows 7 isn't an XP tweak. It's what Windows Vista should have been, they moved away from the Dos format with Windows 7. As for Windows 8.1, that's using a similar architecture to Unix. Though personally I can't stand Windows 8.1, as it's designed for touch screen and not standard PC format and ugly to use.
Actually Chimera can be a good laugh.
Windows XP support ended as of 8th April 2014, you can also still get most drivers for new hardware for windows xp so long as you use an MSI install.
As for government systems, these have been upgraded for a good couple of years. It's their server systems, that are yet to be fully updated. Though Tesco have been the worse with upgrading, as until recently they were still using Windows Server NT and Windows 98. That was the worse upgrade I've ever done.
@IdaBigA
I've got all the original sets of files for King, including the ones before Rich touched them. Will have a look for them, once all our servers are up and running again.