The 35 building block types or galleries simply provide enhanced organization and grouping of the built-in and your custom-defined building blocks. The galleries are yours to do with what you wish. You could create a new building block and store it in any one of the 35 galleries. For example, you could create a group of building blocks consisting of some of your favorite images in a "Favorite Pictures" category of the custom Text Box gallery. By doing this you would take advantage of the Text Box gallery full page preview. I realize that your favorite pictures aren't really textboxes; but hey it is your program, so use it how you like.