Well I have used the patcher on a good number of computers without any problem at all. And manually changing systemfiles is no need anymore with the help of the above linked orb changer and this system replacer app (http://www.door2windows.com/windows-theme-installer-install-themes-in-windows-7-vista-with-ease/). And whenever u wanna go back to the original files, just run the app and choose restore..simple and easy:)
Oh, and if u are not happy with patching files use uxstyle (http://uxstyle.com/)