Which version are they talking about?
If there is a release that uses a CD key, that has not come up in the forum, that I recall.
Request clarification from them on the distribution this is intended for, and argue/repeat that since you have no way to activate the CD key (so it is unused and they can return it to their inventory), you would like to take them up on the money back guarantee.
If a few emails back and forth do not get you a refund, their webpage for the game is misleading enough you should have grounds to dispute the charge with Paypal or your credit card company (keep all email, etc).
BTW, double posting isn't a problem if you're adding additional relevant information.
