The "start-maximized" feature I mentioned is a function of S&T Keys. There is no way to disable it by users at the present time. If you press F2-key, or if you click the S&T Keys desktop shortcut, to start Microsoft Streets and Trips, it will start maximized.
However, if you don't wish to start maximized, especially since you are using it in your home or office environment, starting Streets & Trips by clicking its own desktop shortcut should start it in the position and size of the last session.