If you create a DynamicContentPlugIn with no public properties it wont render.
Steps to reproduce:
This is a known issue in the beta, and fixed to the RTM.
Dynamic content will try to create a hash by using the public properties, and if there is no public properties, the "state" will be empty. The HTML parser will than throw an exception becouse the "state" is empty.
Override the "state" property in on your dynamic content for the beta version, and it should work.