From what I can figure out, the Fuel Control Switches in the 777 are custom coded.
This means that they DO NOT turn the fuel ON (in other words allow the fuel to flow to the engines), even though they are set to RUN, IF your default flight has the Mixture Lever set to Cut Off (0%), as mine is set. So to get the fuel to flow through to the engines, I have to press CTRL+SHIFT+F4 every time I want to start the 777. IF they were set to the default FSX animation tag (lever_fuel_cutoff0 and lever_fuel_cutoff1), I think that when you clicked on the switches, they would work like they should. :-/