Mi spiace per il titolo... pensavo risultasse chiaro.
per il tuo suggerimento...non l'ho tanto capito... 
il codice jquery viene eseguito quando la pagina è ready.. il caricamento del file nel box dropzone.. funziona...
è quando clicco submit che non va...
ora ho trovato un altro esempio che tento di usare...... 
in cui fa....
document.getElementById("testbtn").addEventListene  r("click", function(e) {
              alert('ok');
            // Make sure that the form isn't actually being sent.
            e.preventDefault();
            e.stopPropagation();
            myDropzone.processQueue();
e sembra andare meglio... se riesco a finirlo.. poi posto il codice, così magari è utile ad altri
	codice:
	<form id="form_addfile" name="form_addfile" class="form-horizontal" action="#" method="post" enctype="multipart/form-data">                                        
                     <div id="dropzone-panda" class="dropzone" style="height:200px; border:1px solid #000000;"></div> <!-- This is the dropzone element -->
                    
                    
                    <div class="form-group">
                      <label class="control-label col-md-3">Titolo File</label>
                      <div class="col-md-9">
                        <input type="Titolo" class="form-control" id="titolo" name="titolo" placeholder="Titolo">
                      </div>
                    </div>    
                    <div class="form-group text-center">
                      <div class="col-md-6 col-md-offset-3">
                        <button type="submit" class="btn btn-info">salva</button>
                      </div>
                    </div>
                  </form>
 
	codice:
	$(document).ready(function() {     
   Dropzone.autoDiscover = false;
   
   
    
    var myDropzonePanda = new Dropzone("div#dropzone-panda", { 
        url: "/backend/schede/ajax/ajax_file.php",
        addRemoveLinks: true,
        // The configuration we've talked about above
        autoProcessQueue: false,
        uploadMultiple: true,
        parallelUploads: 100,
        maxFiles: 100,
        // The setting up of the dropzone
        init: function() {
          var myDropzone = this;
            var form = document.forms[0];
          // First change the button to actually tell Dropzone to process the queue.
          form.querySelector("button[type=submit]").addEventListener("click", function(e) {
              alert('ok');
            // Make sure that the form isn't actually being sent.
            e.preventDefault();
            e.stopPropagation();
            myDropzone.processQueue();
          });
          // Listen to the sendingmultiple event. In this case, it's the sendingmultiple event instead
          // of the sending event because uploadMultiple is set to true.
          this.on("sendingmultiple", function() {
            // Gets triggered when the form is actually being sent.
            // Hide the success button or the complete form.
          });
          this.on("successmultiple", function(files, response) {
            // Gets triggered when the files have successfully been sent.
            // Redirect user or notify of success.
          });
          this.on("errormultiple", function(files, response) {
            // Gets triggered when there was an error sending the files.
            // Maybe show form again, and notify user of error
          });
        }
    });
   
      
});