Using ActiveSync, rename the original \MyFlashDisk\MobileNavigator\MobileNavigator.exe to MobileNavigator.bak. Copy these files into that folder.

When you click "Navigator" in the factory menu, it will first attempt to launch an application located at "\Program Files\Navigator\navigator.exe". If it can't be located, it will give an error, then launch the Windows desktop. Otherwise, it will launch the program, and upon closing the program, launch the Windows desktop.

See http://www.oostdyk.com/randy/blog/ for information.