Wonderful graphics and colors.
Main navigation easy enough, but in reference to ghstdrgns's comments you may want to add some kind of rollover text remark to the symbol buttons with a description.
Your main navigation seems to flow within the Flash movie from one scene to another. Break apart the sections and place on seperate html pages to make your site more search engine friendly and allow bookmarking of specific pages.
Also add a contact form rather than rely on the end users email client.
Overall, a nice example of how Flash effects can be used effectively without being distracting.
http://mtheoryit.com