I tried something similar... Created Project Omega which detects kills that way. This was HAAAAAAAAAAAAAAAAAAAAAAAAARD to do! All those lines of code just to eliminate some stupid bugs. But I was thinking wouldn't it be easier if the program detects when somebody joins when this address: 005A53FC (1.23, player 1, for each player you must calculate a new address. I'm pretty sure you know how) is set from 0 to 1. When that player leaves is't set back to 0. So?
I use it alot for my auto-programs.