I'm going to repeat my answer regarding the tabs that I posted on the "Tips and Tricks" forum so that anyone who stumbles across this will see it.
When 3d tabs are added as components, it's usually where the 3d carved component goes all the way to the bottom of the part, so it would cut away a 2d tab. You add the 3d tab as a component so that the carving toolpath won't cut away the 2d tab, which it otherwise would because it goes all the way to the bottom of the material. This is not a "feature" of Aspire, so it's not covered in the manual. It's just a commonsense thing you need to create because of the nature of the carving. In the 3d marlin example, the bottom of the component on both sides of the part is the center plane of the material. The carving goes all the way to the center plane on both sides. If you didn't create a carved tab, then the carving toolpath would just carve away anything that was put there by a profile toolpath.
D&S Artistic Woodworking http://www.dsartisticwood.com