To create a dependent curve-curve point:
If the curves do not intersect, the point is orange, an invalid dependent point.
The point is created at the nearest intersection between the two curves. You can use the curve-curve parameters to trim the parent curves.
While a curve-curve point sub-object is selected, the Curve-Curve Intersection rollout appears.
These two groups let you control how the parent curves are trimmed. The controls are the same in each. "First" and "second" refer to the order in which you picked the parent curves.
When on, the parent curve is trimmed against the curve-curve point. When off (the default), the parent isn't trimmed.
When on, trims in the opposite direction.
Change the U location of the seed value on the first and second curves. If there is a choice of intersections, the intersection closest to the seed points is the one used to create the point.
(Only at modification time.) Let you replace the parent curves. Click a button, then click the curve to replace the original first or second curve.