Downloaded game-serial number not valid

[AMK]

I just Payed for the download version of Penumbra. I went through the whole install process and got to the activation box when I tried to run the program. I put in the serial number given to me on the website under my purchase but it continues to give me an invalid serial number message. I tried it several times copy and paste and putting it in myself. I even rebotted and still the same problem. any one have any ideas for me? I have emailed Gamersgate but I haven't received a reply. It is the weekend and I was hoping to start playing the game. I hope not to have to wait till business hours on Monday. Thank you .