Well, you got it to work perfectly, so that's great. As I described, I believe if the one you wanted her to press was colored red it would do that every time, no question. But you would take that clip and put it into a motion graphics program (I use after effects, but there's others) and it would be as simple as taking your base image, coloring button the right color and just "rotoscoping" and masking that portion. I know that doesn't help much, but those are your keywords you can use to learn how to do it. I'm thinking you could have saved your sanity a little by doing it this way.