Hi!
Do you still get that message (502 bad gateway)? Because on our end, the site appears to be properly connected:
http://jetpack.me/support/debug/?url=www.georgebeckett.co.uk%2Fweb%2F
So PBE should function. It looks to me that you reconnected 7 hours ago. Can you try regenerating the secret email, and then trying again to send it? It shouldn't matter what email client you're using, but it's possible that the emails are getting caught by our spam filter. Can you specify what the subject linein your tests?
As for the site ID, I wrote it more as a note for myself, but you canfind it if you view your site's source while not logged in, near the bottom; it's part of our stats code.
As for walmsleys.com, that site also appears to be connected correctly:
http://jetpack.me/support/debug/?url=http%3A%2F%2Fwww.walmsleys.com%2F
Could you try regenerating the secret email address and write in to it again as well?