The serial numbers / product keys were from our older license system, which was replaced in 2017 with our own proprietary license system. With the new license system, no more serials or product keys are necessary, just an online internet connection.
All our software products require an activated license on your computer, so you can use the products (rendernodes don´t need any activated license!). To activate a license, please use the License Manager application, which is installed automatically with each software installer. The license manager handles the activation and releasing of licenses and you can find more information here: https://www.vizpark.com/documentation/license-manager-reference-guide/
To view your available licenses you can login to your VP account and look for the MY LICENSES section or you can use the License Manager application (1.3.0) which shows all licenses after you have logged in with your username and password.