The white square unicode character is used for marker list where an open box is desired to imply a check list.

The low line unicode character is used for a marker list where a short answer blank list is desired like a true false or yes no list.

The asterisk is used as a reference mark to indicate an omission, addition, etc. In this model it is not being used as part of a footnote, instead it would reference to a non-footnote list of text as might be found in an “annotation.”