Derive the filename from the caption.

client/index.js

 }
 
 function poll(id) {
+  var identifier = preview.caption().replace(/\s+/g, '_').replace(/\'|\"|\.|\?|\!/g, '').toLowerCase().slice(0, 20);
 
   setTimeout(function(){
     $.ajax({
       dataType: "json",
       success: function(result){
         if (result && result.status && result.status === "ready" && result.url) {
-          video.update(result.url, preview.theme().name);
+          video.update(result.url, identifier);
           setClass("rendered");
         } else if (result.status === "error") {
           error(result.error);

client/video.js

 
 function update(url, name) {
 
-  var timestamp = d3.timeFormat(" - %Y-%m-%d at %-I.%M%p")(new Date).toLowerCase(),
-      filename = (name || "Audiogram") + timestamp + ".mp4";
+  var timestamp = d3.timeFormat("%m%d%y_AG_")(new Date).toLowerCase(),
+      filename = timestamp + (name || "Audiogram") + ".mp4";
 
   d3.select("#download")
     .attr("download", filename)