To create a dependent offset point:
While an offset point sub-object is selected, the Offset Point rollout appears.
When chosen, the dependent point has the same location as the original, parent point.
Enables point offset. Use the X,Y,Z Offset spinners to set offset values (in object space coordinates).
(Only at modification time.) Lets you replace the parent point. Click the button, then click the new point on which to base the offset point.