Seem to be getting an error but can't figure out how to drill down further. Typically use Firebug to figure-out JavaScript:
The referenced file post.js can be found here:
http://github.com/allyforce/AF-upload/blob/master/assets/js/_core/post.js
alt text http://img6.imageshack.us/img6/3180/screenshot29201013619pm.png
Sounds like you are trying to reference a control you didn't render. This is often done by accident when people tell it to render a QDialog, but have the dialog set to Visible=false (don't send to browser) rather than Display=false (set CSS style to display:none).