What are you reading from, on the Arduino?
If the values on the Arduino end are in the range 0 to 1023, and you subtract 500 on the Processing side, doesn't that make the range 0 to 523? Why are you then mapping from 0 to 1023 to 0 to height?
Perhaps you should get the handling of data working the way you want using ONE channel, then try to apply it to all 5 channels.
It isn't clear from your pictures exactly which color corresponds to what channel, or color is even relevant to channel. Get rid of 80% of the crap from the picture, to make it clear.