Being a non native speaker, I had no doubt that a developer licence saying "You have rights for royalty free use of our resources for any of your personal or commercial project." lacks the pluralization of project and is meant to allow using it on _any_ of your projects. Designmodo clearly stated it's one licence for one project. They should replace _any_ with _one_.
EDIT: got a reply from them on twitter: https://twitter.com/Designmodo/status/412867217118605313
You were right: "one license - one project."