I have drawn a map of the Kimony Isles (well, for the second time) and it may help with understanding a little more about the geography in A Skeleton Duet. I don't pretend to know a lot about maps and geography stuff, but I did once read a great tutorial by a guy who did and therefore this drawing is halfway credible.
Yeah... The general idea is that they once existed as one big island and then split into several after a big volcanic explosion or just by general sea-level rising. Take your pick, I'm not that bothered really.