It works more realistic than fsx default AP. If you want to change heading put in your desired heading as you did then right click on the heading knob to execute. Once you have right clicked it will stay in heading mode until you select LNAV again or disengage the AP. If you want to change altitude put in you desired altitude then push the verical speed button (VS) and then select your desired VS. You have to manually do this as in fsx default aircraft it does it automatic which is not at all realistic. You can also select desired altitude put in desired indicated airspeed (IAS) and then push the flight level change button (FLC) most commonly used method in the real world