This is with Ubuntu 10.04 LTS, 64-bit, with the default Ambiance theme.
For this test I had maximized the window to cover the entire screen and found I was unable to click any of the elements in the window (i.e. menu, toolbar, items in the binder). Opening the menu with the shortcut key places the menu in random towards the upper left corner of the program and otherwise functions normally using the arrow keys to navigate, as noted by the included attachment.
The program functions correctly when it is not maximized, even if the window is dragged to fill the entire screen. This only occurs when the program is in “Maximized” state.