If you check the laser projectiles, they reference a model like W_LASER_SMALL.alo or one of those. They also have a which has the coordinates 0,0 or 3,0. If you check the W_LASER_SMALL.dds texture file, you can see which color is where. The color on the left is referenced by the 0,0 coordinates, and the color on the right is referenced by the 3,0 coordinates (so if the left beam shown in the texture is red, then 0,0 means the laser is red). I'm currently checking how to change engine glow, I'll put the answer to that here once I figure that out.