"Lights" container
From TrainzOnline
lights { 0 { corona "corona_green.tga" } 1 { corona "corona_yellow.tga" } 2 { corona "corona_red.tga" } }
Defines what coronas are attached to what light attachment points.
In this case, light '0' will be shown with file 'corona_green.tga' (found in the asset directory) attached to attachment point 'a.light0' in the signal mesh. The signals container will refer to it as '0'.