If all you are doing is wanting to change the fuel level after filling the tanks, press and hold the right and left button simultaneously. That will take you to the fuel level page. Across the bottom you'll then see Up, Down and Next. Use the up/down buttons to set the fuel level to where you want it to be, then press Next and you'll return to your home page.
RV-7 Flying as of June 24, 2012
880+ hours as of December 1, 2019. Where did the time go?