Welcome
I've just tried all Tron files which I have, and emissive works well.
Also there could be a problem with this particular model - I don't have it for testing. Please try opening those upk files which are shown in "gallery" - you may see names of upk file and mesh object on the top left corner of the window.
What else could be wrong:
- some textures could be missing - check log for "missing package" messages (shouldn't happen if you're opening the full game)
- you have OpenGL 1.0 mode activated by accident (Ctrl+G key)
- you have a video card which doesn't have shaders