To help determine what the problem may be please update the DataAssist insert, edit the trigger so that it is 'all uploads successful'. After this go to your bindings pane and expand the Digital File Pro group, drag and drop the debug binding onto the page, then save, upload and test the page. If there is any problem with the upload at this point you should see the information printed to the screen, you will need to load the page and upload a file to get the debug info to show details about your upload.
