I have GND but not the dress, I model my own clothes most of the time now. So, I'm just guessing. Were the clothes modeled with the figure in zero pose. If so, this sometimes looks like the clothes are not quite right. Turn IK's off and then zero the figure. You can even up the clothes main body scale a tad to help. You can even turn the body parts that are hidden by the clothes invisible. All these tips help before the magnets.