Normally after takeoff, the buttons in the bottom area (Log engine start and Log off-block) are removed and replaced by an altitude chart for the flight. After my takeoff, the buttons disappeared but the area remained empty. Although the map area above worked normal, I didn't get any warnings and afterwards it turned out no log file was written. During the flight I could not find a way to get it to work well. I probably could have quit navigation and restarted flying but I didn't because I didn't know I did not get a log file. I didn't think of making a screenshot. Version is 4.1.1.0.