THis is a great shot. I think your score was lowered because people were not looking for a portrait in the 'desolation' challenge. It says desolation to me, though. Well done.
The lighting makes this image outstanding. I love the beam of light that illuminates his eyes and forehead, leaving the rest of his surroundings darkened. It really works for this shot, excellent job finding your light. The angle you chose, looking down on him, works really well, too. The eye contact is great. His eyes look right through you.
Composotionally, I might have cropped in a little closer, taking some room off the right of the frame and bottom. This would bring his eyes a little lower in the frame and not so centered horizontally. I think he is a little crowded to the top the way it is. Other than that, I am struggling to come up with a great suggestion to improve this. The light tan patterned shirt is a little distracting, especially where the light hits his shoulder. I might try to burn that down a little.
Please feel free to pm me with any questions about my comments.