After positioning the Auxiliary pivots, you can select the Auxiliary pivot around which you want other objects to rotate. Separate Reach properties for each individual pivot let you specify which pivot is the master at any given time. As you keyframe, you can use the IK and FK key buttons in the Key Controls to specify which pivot you want other objects to rotate around.

For example, if you create four Auxiliary pivots for one effector in the foot, you might first want the foot to rotate around a pivot close to the tips of the toes.

To set a master pivot:

1. Select the pivot you want to define as the master in the current frame.
2. Click IK in the Key Controls window.

This sets the Reach for the selected pivot to 100, and sets the Reach for all other pivots to 0. When you manipulate this pivot, everything else rotates around it. You can confirm that the Reach properties for the selected pivot have been set to 100 in the Properties window.

If you want to set a keyframe in which nothing rotates around the Auxiliary pivots for a body part, click the FK Key button in the Key Controls. This sets the Reach properties for all of the pivots to zero, and all of the pivots have no affect on the effector.