Free edition should be used if you want to use the FREE edition with all its restrictions. However, if you have purchased Kentico license, you can get the license keys for development domains for free (with the same feature set as the purchased license) - in the below options it is the "Ask for non-production key".
If you want to generate license keys for your site, please follow these steps (the account used to log in has to be the account which registered the license's serial number):
Log in to the Client Portal and navigate to the Licenses section. You will see an overview of all the licenses under your account.
For each license, click on Keys (second image button) to see a list of previously generated keys.
Choose one of the following actions:
Generate new full license key: Immediately generate a new license key, counting towards the site limit on the license.
Ask for a domain alias: Submit a request for our approval to generate a license key for any domain, not counting towards the site limit on the license.
Ask for a non-production key: Immediately generate a new license key for a domain name with a special prefix (dev, staging, or test) for one of the existing main domains. For another domain name, immediately generate a 7-day key and submit a request for our approval to extend the expiration.
Upgrade all keys to the latest version: Immediately generate new license keys for the latest version. Valid maintenance at the time of the latest version’s release is required. Existing keys for your current version will still work until you upgrade Kentico and switch the keys.
You can also edit every license by adding a project name or client name.
For more detailed instructions, take a look at the Client portal guide PDF.