I just bought this game tonight from a PC Shop I work at and got the game for about 10$. Well it was used before, and I went on to steams site about Duplicate CD - Keys and they said they do not accept receipts from Used Software Shops. So what am I supposed to do? I was wondering if anyone here could help me out. I can show my proof of receipt, box, UPC, key, whatever you need. I just wanted to try this game out. Would I have seen the 5$ on steam deal, I would have gotten it then. So please, any help at all would be welcome. Thanks.