For the curious, there is the FAQ’s section.
Did you just use EPD or enpkg to install or update your Python distribution? If so, it’s possible one or more of the Enaml Prerequisites got bumped out. Try running python setup.py install or python setup.py develop in the packages Enaml needs if they are not included in your distrubtion. For example, casuarius is necessary for Enaml but not included in the EPD during beta development of Enaml (because casuarius is also under development.)