Light and light-like lights
- lights/light_panel_cool
- lights/white004
- lights/white009
etc.
EDIT: HAD NO IDEA BRUSHES COULD DO THAT! except the thing didn't like the idea of being parented to anything. the glowing remained stationary. it still has to move

Then create a logic_auto with the following output:
- OnMapSpawn > [brush_name] > SetParentAttachmentMaintainOffset > longbrake_02 /delay 0.10 Fire once: Yes
(apart from selecting in the func_brush as Parent the elevator model name!)
...the illumination still didn't want to budge.
edit: I settled on using a an env_projected texture, but i have to say it isn't satisfiying
Another thing you could try is a light_dynamic with a big angle.
Fracture wrote:
for some reason light_dynamic kept disregarding anything that wasn't a model. I checked the wiki and it indeed said it was glitched
if you want to use a dynamic light in portal 2; use an env_projected texture.
Fracture wrote:
Okay, new kind of glitch, the second the elevator moves, the env_projectedtexture disables itself. Literally no other entity is referring to it, it doesn't even have a name yet
is there another env_projected texture in your map?
Does it happen to start at the moment the elevator starts?
Because you can only have one active projected texture in portal 2. So if another one is enabled this one is automatically disabled.
Fracture wrote:
.....yes......yes there is -_-
then check the inputs there
make sure to only have one active at the time 
Fracture wrote:
Okay, new kind of glitch, the second the elevator moves, the env_projectedtexture disables itself. Literally no other entity is referring to it, it doesn't even have a name yet
You may also want to make sure that the proper flags are ticked. You'll need "Always Update (moving light)" to be checked, so the game knows that the light can move. It SHOULD be ticked by default, but it may have been turned off some how.