If you click on the \"L\" icon in MyGeneration and select a collection such as your Tables collection in the MyMeta Tree Browser you can give your tables or columns or whatever aliases. However. This is not a translation mechanism and does nothing unless the templates you are using use the Alias proprety. The dOOdad templates do use them correctly.
Also, in the Samples.User Meta Data namespace of the Template Browser you will see some sample \"User Meta Data\" templates that show how to populate it programmatically as well.