A poster on Somethingawful pieced together the mural from different screencaps. It's like trying to read petroglyphs.
He pointed out this in the corner:
Aliens? It also kind of looks like a submarine to me.
The eye looks like a rhebus to me: the eye for "I", then maybe "m sick" for I'm sick? What does the arrow and the "out" mean? 108 has shown up as the sum of the mysterious numbers, so that's one more number reference. Also, looking at it from a distance, it kind of looks like a warped map to me. Like the blue part in the middle looking like waves. I see the word "stop" on the bottom left.
That arrow is interesting...could it be a cable? Like the cable that is running into the ocean? I always wondered why they didn't try to follow that cable, either into the surf a bit or with the raft. Where could it go, another archipegalo in the region or to manmade platform?
ETA: Or waves crashing on a beach, with survivors on the beach (stick figures)? I keep coming back to stare at these.