I've claimed, davypops, for stuff which went missing in the post and/or got damaged in transit, they paid up OK so I don't know what the problem might be with your claim. They do give a likely timescale on the form - it's not quick because they have to track through the (non)delivery from when you posted it to where it might have gone missing. Have you phoned them? I got better responses on the phone than via the website.
ZebUk - a salutory story - I would never have vital computer data in one place only, it's been said before, to sensible to back it up in a second place too!