I am sure others will help more. It sounds like the keyboard info has been changed. A UK/British keyboard has a different layout to an Australian/American one. Notably, the @ sign is in a different place. 'Bout the same place you'll find the ". So a "British" layout won't help. I think there's a difference between the language versus what the keyboard will understand.
I am sorry I can't offer further, I am learning "mac-speak"
