To take advantage of group selection you must check the enable group selection checkbox. If you do not check this box, questions from all groups will be included on the assessments generated for delivery by Test Pilot's web server component.
Once you have enabled group selection, you may choose to exclude any group by clearing the checkbox associated with the particular group. The include all button is a convenience for editing to allow you to enable all question groups with a single click.
You may also use this screen to assign custom group names to each of the 26 group id's. This is purely a matter of editing convenience and the group names are not used by the web server component. Simply click on any of the blue groups names and edit them as you wish.