Cesar, I am dealing with the same problem. I bought what was advertised as new software, which installed fine, but I'm having trouble activating components.
(I've previously purchased software from other companies via eBay retailers and not had issues with registering and activating those programs.)
If you ultimately can't get the software to work using Cyberlink customer support, you should be able to file a complaint with eBay that the product was not as advertised, which may allow you to get your money back. (In some cases, other options may be to file disputes with PayPal or your credit card company, if you used either of them to make the purchase.)
However, be aware that there are
deadlines by which you must initiate the complaint process in order to comply with complaint restrictions, so do not delay. Credit card companies also may have restrictions in terms of the minimum price for the purchase and whether you already paid the full purchase price, so read the fine print. (In my case, I did not have the time to work on video editing until a number of weeks after the original purchase, so by the time I discovered a component activation issue, I was already past the dispute deadlines.)