Interesting what you say about Beautiful Intelligence. I've now been through three of your novels (The Rat & The Serpent, Hairy London and BI) and currently reading volume one of your newest. So far, I consider Beautiful Intelligence to be your best work and one of my favourite books of the last couple of years.
I can't help but ponder that ending... Although I'm known for ambiguous endings - and I like them in books I've read, I like it when I as a reader have to put lots into a novel, eg Gene Wolfe - I do somewhat regret the ending of Beautiful Intelligence now. Thing is though, No Grave For A Fox is the ending that should have been there on the original novel.