First let me say that I remember this shot from the D&L Challenge and thought it was creative and good.
Composition:
Really nice use of the space. I like the diagonal corner-to-corner line you used - nice variation on the rule of thirds. I also appreciate the fact that not only are the light and dark areas contrasting, but the blue & yellow are as well.
Lighting:
Good, but perhaps a bit harsh. Some of the highlights, while aren't blown, are a bit bright. However, the contrasting light and dark areas compliment each other well.
Focus:
Good, but not quite tack sharp. The added texture of the underlying material is a nice touch though, and adds yet another layer of contrasting elements (smooth surface vs ribbed).
Overall:
A strong entry IMHO. I think the score probably suffered a bit because of the title - there were so many "Dark & Light" entries. I think that this particular image was underrated because of the varying levels of contrasts you presented.
I also looked through your Portfolio - you have some fantastic stuff! And 200+ challenges? Wow.
Clever use of light and dark. Interesting grooved base - is that plastic? I think this might have more pow if done in black and white although the high contrast of the blue and yellow is ok by me.