I would like to get the Flash fallback for mediaelement.js to work, but it only shows a black area saying \"download file\" in the upper left. The video markup I generate l
As ivan_pozdeev stated, you do need to specify a src tag in your video element. However, you do not need to provide multiple sources for MediaElement.js to work across different browsers.
In your case, you can provide a single .mp4 file and it will work across browsers (see Step 2: Option A at http://www.mediaelementjs.com) as long as you have Flash or Silverlight installed (i.e. ME's "Fall-Forward" functionality).
"Download File" will show up when HTML5 is not native to the browser you are using AND you do not have the respective plugin (i.e. Flash or Silverlight) installed. In mediaelement-and-player.js, break on line 162 (var pv = this.plugins[plugin];) - if "pv" has a value of "0, 0, 0", MediaElement has not detected a plugin and you will receive the "Download File" link.