Lit from within
Hi,
You can use opaque glass and have a night texture that looks like it is lit at night. OR...
I have successfully done this, although it was for FS2004, where transparencies were much easier.
I made the building with semi-transparent glass.
I made an interior for it, and that interior had day and nigh (_LM) textures.
For the interior I made a box, removed one face, textured it, and turned it inside-out by just moving the bottom vertices through the opening.
At night the lit interior would show through the semi-transparent glass.
Actually, when I did it, I became momentarily hysterical, because it looked very cool, or so I though. Later I abandoned the process: too much work for little impact.
The outside of the building also had LM textures, but that was just to show some entrance doors, that sort of thing.
I haven't tried this in FSX, and I don't know whether it works with it.
Fern