Thanks everyone for the advice/comments! It's made me feel a lot better and slightly more confident about the application. We're in the middle of writing out our statements about the history of our relationship at the moment. Should we include all these explanations with bits of evidence in these statements? Or in a separate statement (e.g. one for financial aspects, one for nature of the household).
Also, how should we present email correspondence in our application (how do we get emails certified?) Do we just print them out, or are screenshots better?