so, im asuming you have the dll? if not, look at the very beginning of this post, and get download the rar or zip file (use winrar to extract, if you dont know what that is, just google it. im positive it will come up, and its free)
now, we have the DLL, so we need to inject it. follow this link to get the PERX injector:
use this, and browse to the place that you put the DLL. then run PERX as admin, and go to the place where you extracted the DLL. select it, then select the option that is 'auto inject' and just run combat arms as admin. It should open, and show a menu with the hack. if that still doesnt make sense, tell me, i can TV you and try to help.