If you create a new page in the dnn portal and add an existing module (Form Master 1.5) to the page so it is a reference of the original form.  It causes the files to show as a duplicate.  If you remove the form from the page.  And go back to see the files it shows correctly.

Is this a quick fix?

e.g. Page 1                               New Page
Form Master 1         Reference ->Form Master 1 on Page 1

Shows Files as
ID  File name
1    test.txt
1    text.txt

Remove the refernece on the new page and it fix's the issue.

Go to Host --> SQL. Paste the SQL below into the textbox and check the "Run as Script" checkbox then click "Execute" the duplicates will be gone. This will be in the next update.