Hi, thanks for the tutorial it solved the Centre of Gravity calculations for me!  I enter the gross weight into the FMC and the FMC calculates the ZFW! Its the other way round but works!

I use the Just Flight 757 CS DVD rom version. Just awaiting the much hinted at patch that will (please) address some issues like no VOR deviation indication in the HSI VOR and no weather radar (just a "TEST" message!)

Hope the patch will make this a superb sim rather than just a good one ;)