Love the new interface. Very clean and classy.
Suggestion 1. Leave the main menu open all the time on the top or left. Alternatively, provide a clearly-marked, obvious button (best if in the upper left) that would expose the menu without closing any open windows. As it is, the user has to click the HOME button in the lower left to expose the menu, which closes all open windows. Naive users will be confused.
Suggestion 2. Re-size the interface to fit the window it opens in. I have to scroll down to see the buttons on the bottom even if in a maximized window (running on a MacBook Pro 15" 1440 x 900).