When you are using your walking foot, the machine is in control of the stitch and feed of your quilt sandwich, UNLESS there is too much weight hanging on the quilt. I stop very often and puddle the quilt around the machine so there is no weight pulling on the quilt and also keep it as smooth as possible. You don't need to do any pulling or pushing on your quilt. Machine is working just like when you are doing regularlly sewing with the walking foot acting like feed dogs on top of the quilt so all will be fed through evenly. Sounds like you have drag on the quilt or are helping it too much. Good luck. I know how frustrating it can be, I can't free motion to save my life. Never have been able to do anything tha takes any co-ordination.
Robin in TX