Zillmer
Ill try to help you im a keen Flight simmer myself too, im a Licenced Eng on the 777/744 so ill blow the dust off my notes and try to answer your questions best i can.
Q1. Technically only the BATT No2 bus (Only has one Baterry, the bus is split into 2) , Standby power is automatic on the 777 from main batt bus, there is a manual switch but its on the maintenance panel and is not often used. Ill need to look the schematic for a fuller answer for you. With batt switch on all you see in the flight deck is 2 eng gen drive lights, the aircarft is dead otherwise.
Q2. off the top of my head No, the APU gen selection on the 777 is AUTO the switch remains in. When in the simulator on training we had many things failing, is takes some doing to kill this aircraft electrically! being a very electronic software driven aircraft power interuptions are not liked so its well designed to avoid them.
Q3 Need to check that one.
Its midnight when i answered this so sorry if it reads crap just finished shift!
Private MSG me your email.
Stu.