Hello, please ignore the above post. While it is correct normally, I know for a fact, in this case, it is not an issue of piracy, or likely at least.
Cosmi released ALOT of corrupted game disc's awhile ago, you mentioning it being $10 flags this as being the problem. I myself had this problem from a $10 disc I got at a Wal mart.
There IS a solution to this, however I cannot list it here.
Please go to http://www.lucasarts.com/support/
Via the tech support page, submit your problem and they should get back to you in a few days with the remedy.
Expect about a week of time before you can play, however it will work once it's done.
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