Just watched it again this morning as there are bits you miss out on first time around. Police waiting at the canal border, the Yorkshire border LOL, a nod to getting across the state lines in the USA, it is all very clever stuff.
Another thing I noticed was the knomes coming over the hill, but was in fact traffic cones on the back of a lorry, he he he. Mind you I was a bit intoxicated when watching it on Christmas day :D