Composition - This particular picture is real real close to being very good. The composition is pretty good. There is a little naturally occurring noise that I think takes away from the image considerably. I think the ring of bubbles and stuff over the top of the yolk and around that arc are very distracting. I think if you could remove those, you improve the composition substantially. There is also a small bunch of them on the bottom right of the yolk that would be better if removed. The ones in the white of the egg are a bit distorted and don't look so much like grains of sand. I think they can stay and not be too distracting. The angle and the macro effect really make this picture.
Technical - I think this picture, well focused would've done much better. The image is just a little bit short of sharp. It may be just one more "sharpen" away from that actually. The exposure could've been just a little more too to really bring out the yellow of the yolk. Its close. That may be possible to fix with PS as well.
Overall - A good concept for a picture. I think with a little honing this will be a really nice image. I think your pic was graded a little harshly probably due to the sharpness. I'd be lying if I didn't say that was a sticking point of mine too. Hope this could be a little helpful for you. Good luck in future challenges - Inspzil
nice detail. I would like to see it a bit brighter. slight exposure compensation +0.3 may have brightened it a bit and still keep that "outer space" feel