I have attempted to download Fallen Enchantress five separate times now, using Firefox and Chrome. Each one completed at 3,652,857KB, however, each one also fails to extract with the "File is corrupt" error message. FC also shows me that each one is different from the others, so it's not like your cache is serving up the same bad file every time. More disheartening, your cache isn't serving up the same file each time period.
The Internet isn't supposed to work this way. I don't know what to do about it.
I also tried putting my serial into Steam, hoping that I could download it that way, but that doesn't work (it's not recognized as a valid key by Steam). Is there some way I could register my game with Steam and use their service? Less load on your servers, working program for me - everyone's happy.
3.8 GB is a reasonable download, but having to do it a half dozen times the novelty is wearing off.