Cut shots are going to be a cause of the hips and shoulders square at impact...you need them open to the target...i.e. getting around more prior to impact. This extra rotation is the one essence of the benefit of the drill that you get more rotational power.

You asked a lot of questions and I will try to answer as best I can:

1) At the top of the back swing, both wrists should be cocked and the right wrist should be cupped??
Yes

...left wrist should be flat or slightly bowed?????

A: I like the left wrist slightly bowed because I have a stronger grip. A weaker grip will see the left wrist a bit flatter (less visible bow to it).

2) That being the case, how should this happen in the back swing, as we should only cock in the back swing, as cupping will cause wrists to roll???
No, cupping will not cause roll. It only sets the right wrist into it's position. Rolling is a natural rotation of the arms as the shoulders take the club back and through.

so when do we cup the right wrist???
In the drill, you preset it at setup. This is because the drill is designed for those that swat. Once you master the drill, you are free to preset, or to let it set into the backswing...your choice.

if the right wrist is fully cuppped is the club faced not then closed at the top.
No. If you see a closed face, you are most likely doing something else to cause that.

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I'm a golfaholic, no question about that. Counseling wouldn't help me. They'd have to put me in prison, and then I'd talk the warden into building a hole or two and teach him how to play. ~Lee Trevino