How do i get a working file replace form from a concrete5 block view (so not in edit mode)

I now use the following:
echo '<a class="dialog-launch" dialog-modal="false" dialog-width="300" dialog-height="100" dialog-title="Vervangen" href="/tools/required/files/replace?searchInstance=file1344089826&fID=' .$item['fID']. '">Vervangen</a>]';
echo '<script>$(document).ready( function(){ $(".dialog-launch").dialog() } )</script>';

This presents me with a nice dilog with upload form. But when I submit this form i get a empty page. The file is replaced so the processing is working. I only need to give feedback to the user...