I finally figured out a way to score FK's. If your close to the keeper (and that means having a 4-man wall..!). Curl the arrow opposite to the keeper, that is if the wall is in front of you and the keeper is to your right you curl it so it looks like a "C" (exactly the opposite if he's to your left).
Do not chance the direction on the arrow. You can also tab the height once (just a bit) and the just shoot the ball almos 95% green. They'll go in 75% of the times.

Now, whene you'r far away from the keeper (3-man wall) I don't know yet how to score consistently....
If anyone of you know let me know..please...!!!