Here's another way to fix the River Dance Effect from Walk Designer. select the Foot with IK ON open the Graph View (Ctrl + Shift + G) Select the Y Trans for the foot. You will see the Spikes in the graph. Use the mouse to smooth the spikes out. You may also explore the foot Bend, Shin Bend and Thigh Bend Graphs. You may find spikes in there too. Or, get the Millennium Walk Designer. Then she will be able to walk, and in high heels too. Happy Rendering!