2 Cthulhus
Ok, I'll prepeare dark textures for those areas.
...but those lighted corners was co cute... :)

Back to overhead - I've found that this issue refered only to 757-200 model(I've never flyed on it). In 757-300 overhead is OK. Probably the reason in model itself.
Try to play with additional 4(panel) lightsource coordinates to automatically highlight overhead a little when Panel is on.
Probably this will help(add to lights section of aircraft.cfg of 752): light.XX = 4,  66.00,   0,  3.5,  fx_vclightwhi


2 Space shuttle Nope, this is old-good FSX bug. Try to use Flood 1 and 2 without Panel switch.