Thanks!
Scoring is comprised of 3 parts:
1. Exact pixel to pixel matching. (If you have the correct colored pixel in the right place)
2. Amount of pixels of each color in the entire image compared to the target image. (# of red pixels in your image compared to # of red pixels in the target for example)
3. Basically the same as number 2, but we do it over 4x4 pixel chunks. (Each chunk is pass/fail, you either have most of the needed colors or you don't)
These three scores are combined then scaled to be from 1-5 stars.
So the "meta" is make sure you have the right colors in generally the right area, and the pixel perfect test more or less judges how well you did at making the correct shapes.