I've kind of kept arms length away from this shooting, trying not to get overly dogmatic about it. But I have a few questions that I have not heard addressed.

#1 According to yesterday's testimony, Martin was shot in "the chest area" and was still (barely) alive when the first responder tried to revive him. He testified that he rolled Martin's body over and gave him mouth to mouth.
#2 If Zimmerman is correct in saying that Martin was pounding his head on the concrete, then Martin was on top, i.e. you can't pound someone's head when it is at a distance. (Incidentally, were the two men curbside? Pictures show two small 'lumps' on Zimmerman's head that would seem to indicate an edge to the concrete.)
#3 Since Martin was shot in the chest, should not Zimmerman have been covered with blood? According to the first responder's testimony, Martin's heart was still beating, and therefore pumping blood. Zimmerman "was wearing red clothing"- does that explain why the blood was not the most visible thing present? The early accounts that I read never mentioned blood on Zimmerman, nor did I see any pictures of it.
#4 Zimmerman was taken down to the precinct station to make a statement and then let go. Presumably this was before he went home and changed clothes. Will there be testimony by the police department describing Zimmerman's clothing?
#4 After Martin was shot and Zimmerman was lying beneath him, presumably Martin's body was limp. What is the most common scenario in sliding out from under a limp body? Would one thrust it to the side and slide out? Or would one 'buck' it off?
#5 Did Zimmerman examine Martin's body after the shooting? In that case, it would be logical to say that he turned it face up. Yet, the first responder found it face down.

All that said, I can imagine that one's thinking processes would be so chaotic, so fragmented, that any logical sequence of events would be impossible.
As I said, I am come late to this subject- after all it is now in the trial phase - but please bear with me. I'm sure there is information out there that I don't know.