The background buttons on the HyperArchy Element Card, and the background of the card itself, contains all the HyperTalk scripting that makes HyperArchy work. Therefore, every time an Element Card is copied or created, all the functionallity needed to support it is cloned along with it.
The linkage fields, also on the backgroung of the Element Card, are the glue that holds the hierarchical database relationships together. The control buttons read and modify this information, as cards are created and deleted.
HyperArchy only supports balanced, homogeneous database structures. An upper level stack can only attach to Child Cards in one specific Child Stack. All the cards on any level should have the same background. You can probably violate this with some careful use or some extra programming, but that is not the way it was meant to be used.