by Boikat » Fri Mar 25, 2011 12:10 am
I don't have that particuar addon, but some things to check, as far as sound goes, is the sound file of the aircraft. Many add-ons "alias" the sound to one of the default aircraft. In the case of airliners, it's usually the 737-800.
As far as the cold dark cockpit, double check to see if the download is specifically meant for FSX with SP1 &2, or Acceleration. Some add-ons that were specifically designed for FSX Acceleration will not start ( or have other problems) if you do not have acceleration installed. (At the very least, SP1 & SP2 should be installed anyway, as it improves the sim, in general. They are both free).
Just something I would try (More out of curiosity) would be to rename the 777 "panel" folder, then, then drop in the one from the 737-800 and see if it works.

"I reject your reality, and substitute my own" Adam Savage, Mythbusters