Are you sure about this? It has been a number of years since I tried it, but I put a Europe High disc (left over from someone else's European Delivery) in my E46 / MK IV and entered an address in the UK. After a little while, it told me it couldn't compute a route from New York to London.

However, if I used the "destination map input mode", I could scroll the map over to Europe and view roads, etc.

Of course, an out-of-region map isn't particularly useful.