FileMaker tech support is not supposed to charge for installation issues so you might want to call them if you don't get a timely response that helps you out here in the forum.
Thank you for post.
This is the expected dialog window when installing a FileMaker Pro upgrade license. If the qualifying product is not already installed to the same computer, then you will be prompted to enter the license key for the qualifying product. In the case of installing FileMaker Pro 12 this will either be a FileMaker Pro 11 or FileMaker Pro 10 license key.
If you are unable to locate the qualifying license key, then please contact customer support for assistance at 1-800-325-2747 in North America or +1 408-727-8227 (Outside of North America).