Strange level, strange questions

[Kamaeru]

So I found this level on Graal2001, it's the Bomy Gang meeting room containing the Bomy Gang tag helper and things as such. I had never seen this level before today.
I'm not certain who is the creator of this level, but I am certain that Stefan Knorr probably knows what I'm talking about.
What appears to be going on is that someone used a script to invert the colors of pics1.png to look super freaking sweet. Reminds me of Moonside (if you've played Earthbound).

Only thing is, I can't find a script anywhere in the level that is responsible for this! Could the script be only accessible by opening the level in .txt?
Would anyone like to try and figure this out for me?
Is the editor just glitching out?

Also, does this belong in a different forum?