What finally worked for me was to open the console and typeI'm having the same issue with a US keyboard. The above fix, does allow me to choose the keyboard and creates a keymap file in /etc that says only
us.map
However, the Y key still types a Z and the Z key still types a Y.
"setxkbmap us" ( without the quotes) and press enter. If it works, you will see # with no error message.
I presume "setxkbmap uk" would work for UK users.
Hope this helps.
Scott