Weight problems
When u make a flight plan the fuel is already accounted into the flight plan...if you Adjust any fuel by either:
An aircraft capacity value change - from the settings
Or
Change the value of fuel being carried (this can be done on the flight plan sheet on the right side of the table in the top row - a value will be already placed here that lists the exact amount required for the trip/leg of your current flight plan)
Or
Changing values From the weight and balance set up
When you change any fuel, for example saying you would like to carry 110l instead of the 54l that ozrunways determines that is required for the leg or trip, it will be added to the flight plan as weight on top of your loaded weight (i think ozrunways calls this LW In the app), and your mtow will also increase....however if you select that for the flight you would only like to carry the exact amount that ozrunways says is required the Loaded weight and MTow will add up correctly.
All it is saying is, is that whatever ozrunways determines is required for that flight in fuel weight, will be the difference between your no fuel weight and your Mtow. Any additional fuel will not be counted as fuel weight, it Will automatically be included as load (the same as pax and bags).
Hope this helps