Why would you have auto LNAV for G/A?. If the G/A is climb straight ahead = RW track then HDG SEL is required. Also, I seen many missed approach routings programmed incorrectly. Often there are 2 criteria and the turn should be made at the first occurring one. The FMC can not program this and usually it defaults to the DME not the ALT above for the turn. Thus LNAV would not be correct.
I can only vouch for the sim and the active WPT, which maybe behind you, remains so even after TOGA. This is FMC 10.8. No idea about customer options.