You can take it to the bank that neither Zimmerman or his attorney's have any interest in a lawsuit for false arrest... They both know the facts of the case and they understand that the DoJ still can bring the same charges under federal hate crime law... They also understand there is a good chance that Martin's family, after it has had a little time to digest this bungled verdict, may be bring a wrongful death suit against Martin...
So, there won't be any such action coming from the Zimmerman case... Plus, it would be a civil suit and that would expose Zimmerman to the witness stand... He wouldn't have a choice but to testify or risk losing that suit with whatever cash amount would be attached to it...