Difference between UK, and USA is simple
we have different spelling (i'm from UK) for certain things like - Colour (which in your language is color)
we also have a different keyboard layout
we have our @ on the ' key
other than the odd spelling mismatch there is no real difference between language English US, and English UK
so my suggestion with this is not to have the setup running in both English UK and US because during windows setup (in uk) we use the language US makes it slightly easier