Using the Z string terminator trick we've given meaning to the rightmost column in the red channel as well. The rightmost line says "A Koan" which is a zen riddle or puzzle.
A novice came to a master
A novice asked how to find
A solution to riddles hard
A reply from a master was
A novice should search through sand
A novice should so find a boulder
A novice should search through air
A novice should so find the sky
A novice should search through water
A novice should so find the river
A novice was enlightened
Given the red message starts all the way at the right and the green message starts all the way at the left it suggests we've completed the red and blue messages (of this format anyway). The blue map is (at this point) still unsolved.
Since we now know this was a riddle, what @Jacob Waite suggested might be helpful in solving it. He pointed out that earth, air, and water are all mentioned, but fire is not...