The only time I give her a treat now is right at the end when she's done her final stand at the end of her walk. I tend to use the bag as a form of attention, if I put my hand to it, she's right there looking at me.
As for her leaning back, I was advised at ringcraft to put her front legs on the edge of the grooming table and tempt her forward with a treat. It does help a little. If I go round to the front of her like advised, when a judge is at her rear, she wriggles and won't stay still. If I put a treat in front of her, she just goes mad for it. She has got a nice stand when she puts her mind to it, but it's getting her to hold it. I guess it's practice, practice and more practice.