Hi Filippo,
thanks for your post. I am sorry to hear about your laptop.
You do not have to buy another license. I have forwarded you the email containing the license that you purchased. Please, download the QtFuzzyLite software from http://www.fuzzylite.com/downloads, and make sure that you install the Microsoft C++ Libraries suggested in the download links.
Let me know if I can help you any further.
Thanks again for your support purchasing a license of QtFuzzyLite.
Cheers.