When I edit control points, why don't the sections update?

The sections will not update unless you use Orca3D's custom control points. Turning the standard Rhino control points on and editing will change the shape of the surface, but you'll need to update the sections manually, using the Orca3D Sections command.

In the Hull Assistant, why do some input values create crazy shapes?

The equations that are used to generate the 3D hull shapes degenerate with certain conditions, such as various values being set to 0.