if you are going to use a recordset to tell which file to download, you need to create a way to filter the recordset.
what i normally do is to have a recordset that is used to populate the page. create a form with a submit button and a hidden element, set the hidden element initial value to use the ID column from the recordset. then add a repeat region around the form so that a separate form is created for each record.
you then need to create a lookup recordset that is set to filter the ID column on the hidden form element value
in the download behavior, use the lookup recordset instead of the one that populates the page.