Hey Liam! Microsoft release a SP1 (GDR1 called "Update 1") for Win8.1 at 4# April. (Official 8#). Example: http://www.tomshardware.com/news/windows-8.1-gdr1-windows-9-windows-phone-threshold,25861.html My ask, what you think about maybe Slipstream-Support in WinToolKit? It exist some pre-releases (beta) for you can test it with maybe. What you think if or when its possible this feature? That would be awesome. And have anybody a hint when possible available a Win8.1.1 MSDN ISO? Greez BTW: Mhh... GDR1, maybe it exist LDR1? Of course I wanna have it!