How do these laser work????

Hi guys
I downloaded these laser sensors and installed them but they dont work. What is haopening is that theyare turned off and i have no clue how to turn them on!
Heres the link to the lasers:
Can somebody help me?

“Uploaded 1185 days ago” It’s a very old addon and it could be broken.
Also it’s a sensor that emulates a “key press” when something gets close to it. You can change the length of the laser sensor with the “length” thingy.

i tried that already
i think its too old