Elevator lighting
I meant to say: upload the map to the workshop, subscribe, see if the videos are still black. Some things won't work locally but only on the workshop (Cave Johnson speaking or intentionally not speaking for example).
OK, I checked your map. First of all, I asked you before to check out into the instances, to check for the logic_relay that surely activated the light obs_room, check about the "@" prefix in its name and trigger it, but I think you didn't do at all. I don't like to write such a lecture and to have a feeling that the OP didn't even try anything suggested or put interest in solving his/her own issue... but still:
1. There IS a logic_relay into your obs_room called "@relay_lights_on". I took that trigger brush in your map's entry and correct your output for this one:
- OnTrigger > "@relay_lights_on" > Trigger.
So your obs_room lights work out now. 
2. About the elevator, the env_projectedtexture works fine, but the videos don't. You are seeing that black tiles because they don't even turn on. I tell you again: it is because of the script. Valve released a new script "video_splitter.nut" with their DLC2. It's located into portal 2/portal2_dlc2/scrips/vscripts/videos folder, and it has priority over the old ones overriding them...
My fix:
As I know that the old script works fine, all I did was to take it from portal 2/portal2/scripts/vscripts/videos folder, and in order to make it work, it's important to give it a different name and place it in a different location than it is now. I named it "jose_video_splitter.nut" and located into a new folder I made: "portal 2/portal2/scripts/vscripts/josepezdj"
Now, again, you have to go into the instance as I told you before (it's the "arrival_elevator_logic4") by clicking "Edit Instance". Locate the logic_script entity that manages this script (it's on the playerclip textured brush) and tell it to use your brand new script called "jose_video_splitter.nut" into /josepezdj folder... am I explaining clearly? 
So your videos show up now.
Proof:
It is important that you understand what I just did in order to do it yourself. But anyway, I'm attaching your map modified and the arrival_elevator_logic instance modified, and even the script with different name (place it where I said above). Would you try to manage yourself to make the videos to work for the departure elevator? I know you will
useful tools and stuff here on TWP 
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josepezdj, thanks for your patience and help, but please let me explain myself.
I'm not lazy or not trying to fix my own problems. I've been doing Source mapping for a year now but instances have been impossible for me to understand. Every time I come back to Portal 2 I rage quit within days. I don't know if the wiki articles I was reading were poorly written or whatever but eventually I got too frustrated and needed to have someone personally show me an example in my map to understand the whole thing. I didn't know what they meant by the "@" pointing to the entity directly but now I get it. (Oh, and I'm a male. 
)
It's ok dude. I like to help, but maybe it's just that I sometimes lose my patience
One thing more I forgot: you should pakrat the script into the .bsp in order to make it work for other ppl, ok? And do not forget to correct its path once into the bsp with pakrat.
I hope that you let me know if you finally get the deparutre elevator videos to work
useful tools and stuff here on TWP [spoiler]
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@josepezdj Amazing fix here, very detailed and worked right off the bat. Cheers!
Thanks mate! Glad to hear!
useful tools and stuff here on TWP [spoiler]
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