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Licence Note:
Personal licence = You can use the plugin for your own personal, private web site.
Developer licence = You can use the plugin for all web sites (commercial use).
Domain licence = You can use the WCMS for all your domains (commercial use).
Server licence = You can use the WCMS for all your server (commercial use).
Upgrade = You have bought a personal licence and you would like to change to a developer licence.