The Move up/Down function is only active when the Bill Heading is part of a Title Bill.
To Title A Bill:
Open the Bill Summary Select Allow Changes, Select Add
Enter a Bill Heading name and number, and then select Title
The Heading will go bold and then additional bills can be added with the same bill number, or existing bills have their bill number changed to match the Title.
Note: There are only 2 levels allowed for creating a Bill Summary
The Title Bill Heading would be in bold and the Bills underneath can be highlighted and moved within the Title Bill.
You can renumber Bills that are not titled to reorder them but you must select Allow Changes first and cannot use the same number twice.