Which application/mover should I use to evaluate the ddg between apo enzyme and enzyme binding with transition state?

Hi everyone:

        I used Enzyme Design application to get a series of enzymes with ligand(transition state of my target reaction). Now I want to inspect the free energetic change upon the protein transition state binding. 

        So I first look into the ddg_monomer application, and I find this application is suitable for comparing ddg energy between wild-type protein and its mutant structures. This can't meet my needs.

        I am wondering if there is any application can evaluate the ddg between apo enzyme and enzyme binding with transition state? Any suggestions would help. Thanks for you time and effort.