You need to adjust the little centering pot inside your 5200 console. I made a masterplay clone for myself and it basically didn't work at all until I properly adjusted the little pot inside the console.
I used Super Break Out to make the adjustment but Missle Command will work as well, just turn the thing a few times back and forth and then, with your redemption plugged in the controller port, adjust it so that the paddle/cursor is centered on your screen. After you do this your Redemption should work just fine. I know on some games, Galaxian comes to mind, you have to kinda thrash the stick around a few times before they work even after you make the centering pot adjustment.
Edited by Prodos8, Sun Feb 12, 2012 7:29 PM.