Actually it's pretty easy. You can start the small claims process online in the UK for as little as £25. You can be awarded in absentia, so you don't even have to turn up. Bear in mind most cases are not contested so awards can be pretty swift.

I made a pretty comprehensive post about it here:

https://bitcointalk.org/index.php?topic=314402.msg7371136#msg7371136.

Everything else you said is pretty much spot on. Document everything, even forum posts (probably one of the reasons Fiaz removed his posts)

You don't have to wait until they fail to deliver, you are entitled to cancel at anytime for a full refund under UK law. If you want to wait until the end of July that's up to you. Good luck