Umm, I developed a bit for A**** Gunz (won't put the name here) I remember. I'm very experienced with DirectX9 client-sided games, more GunZ-game wise mostly it's just understanding the classes and what classes are responsible for what, it's very easy to me, I also noticed it still uses hungarian notation and I can work with that too!
A simple bit of explaining would do that work, if needed at all, if you don't want to, it's not needed I can handle it on my own.