No, the CD#1 is your "key". Put it into the DVD drive when prompted (as it says on the screen), this will unlock the program.
X-Plane also asks you for a key, but only because recently (not some time ago, when you bought it), X-Plane is also sold with the option to have an unlock-code, since some people don´t have DVD drives on their computers anymore...
If all else fails, you should contact customer support at Laminar Research, be ready to provide proof-of-purchase.
Good luck, Jan