Why Gun Control advocates will end up with egg on their face once again...

[Oneka]

68. Don't be so sure

Don't be so sure of a conviction or even a prosecution in this case.
The antis, have been salivating for years for a case like this.  The media attention to this case is plenty of proof of that. Many police and DA's don't like stand your ground laws. Don't be surprised if they fail to prosecute this case to further their agenda,  of getting this law repealed.
They will likely use the same law you linked to in the OP.
766-041 (2) B, is the relevant part of the statute.
If Zimmerman asserted that he attempted to withdraw from the use of force, and the kid, didn't stop hitting him, he likely has a good chance of avoiding prosecution at all. 
The cops and DA can very easily stop any prosecution before it  begins, then use the SYG statute, as justification  for doing so. Don't be surprised if Federal pressure, and FBI assistance wane, as they realize what an anti , wet dream, they are sitting on with this case, if only they don't prosecute.
The best thing that could happen in this case , would be for the media blitz to continue. The pressure could force the Florida authorities to do the right thing and prosecute this case.