Yes, British English can be a shock occasionally, as all authors tend toward Americanisms (and I say that as a Brit).
Really? None of the Brit authors I've read have tended towards Americanisms. And over here it's pretty much always 'lorry.'
On topic - I've never read Narnia. Was put off by all the Christian stuff... though I imagine that's not off-putting to a Parson. I did enjoy the films though, though I admit that's mostly because of Ben Barnes.