Regarding level 2817: I created piece c2 from a painting I made with my friend Beth then I flipped it and inverted the colors for a2. I don't like to speak for others but my guess is that MRM used photoshop or GIMP to create his pieces (a1 and c3) sampled colors and used the blend tool in order to blend seamlessly with my pieces. My interpretation of a1 is a monkey looking at the viewer through a hard rain storm. For c3, I see a table cloth that is perhaps also fields of crops or grass.
Tell me what is it that makes you so obsessive about this question and what exactly is it you want to know? Have I helped at all? Is there any way that you would consider not spamming the board so much?