Select the KneeIK handle and shift select the AnkleIK handle and group (CTRL + G) those two together and call that group "BallRotate" and move it's pivot point to the Ball joint.
Select the ToeIK handle and group (CTRL + G) it and call this group "ToeRotate" and move it's pivot point to the ball joint.
Lastly, select the FootRotate Group and group (CTRL + G) that to itself again and call the new group "FootCTRLGroup" and move it's pivot point to the heel joint
Well, we are finally done with all the grouping. That wasn't too bad now was it? You should now have five groups in total. Lets move on and create the foot controller that will move the foot around and set up our set driven key.
4. Foot Controller
We will now create a basic NURBS circle and use that as our foot controller. Create a NURBS circle (Create > NURBS Primitives > Circle). When creating the circle go into the option box and create it in the Y axis. Now switch to the top view and re-shape the circle by moving and scaling the points to get a rough oval shape that fits around your foot. Name the circle to "FootCTRL" and delete it's history (Edit > Delete by type > History) and then freeze it's transformations (Modify > Freeze Transformations).
We will now connect the FootCTRL to the FootCTRLGroup that we made earlier on. Lets bring up the connection editor. Connection editor is found in Window > General editors > Connection Editor. Once the connection window opens, select the "FootCTRL" circle and load (You load an object into the connection editor by clicking on the reload left or reload right buttons at the top of the connection editor) that into the left colum. The left column should be the output column, if not, then reload it in the right where the Outputs column is. Once you have loaded the FootCTRL in the outputs column, select the FootCTRLGroup and load that into the Inputs column. You should now have the FootCTRL circle in the Outputs column, and the FootCTRLGroup in the Inputs column. (I recommend you do the selecting of the FootCTRLGroup in the hypergraph).