It would be really convenient if the "Store purchases" list in STO files could be displayed as a panel of checkboxes instead of individual items. I know as far as the file structures are concerned, NI typically only uses the checkboxes for bit fields, but the ease-of-use would be greatly improved IMO if something similar could be implemented for the "Store purchases" dword array as well.
The "Store purchases" items are defined as a dword array of arbitrary size (in contrast to bit fields which are always constant in size). You can freely add or remove items to/from this section and the list of item categories can be unsorted (as it's done in a couple of STO resources added by BG(2)EE).
Furthermore, the size of this section is practically only limited by the number of supported item categories (which is around 74) and can theoretically support up to 4 billion entries. That's why I don't think it is possible to encapsulate the whole section into a single data type without losing some control over it.
The best I can do is adding a summary of the "Store purchases" list to the View tab.