Regarding the flight and system issues.
Many tips / workarounds are devided all over the 777 forum.



Sudden airspeed loss :

Shift + H



Gear missing on 300- models

Re-install with manual offline actiivation



No nav, strobe, taxi , etc lights

Make sure the generators are on



Modified 777-200LR airfile for improved spoilers drag

http://captainsim.org/yabb2/YaBB.pl?num=1360045061



Fix for reference speed

http://captainsim.org/yabb2/YaBB.pl?num=1359109073




If you have a good solution regarding the VNAV and AT issue pleasae post it here too.
Also point out if it is for the 200 or 300 version.