Can I trust mrtoken and webcheque if I want to buy HoTs and download it? I mean what if I pay first and then the download fails. I had this problem once with Blizzard when I paid for Wings of Liberty but the download failed, it was a nightmare to explain it to them but it worked out in the end. First I got my money back and then I paid again for the new download, a bit confusing but yea it worked.
Where did you download Starcraft 2 from? If you buy the game on Battle.net you can always redownload if it fails...