Please read for an updated status on RailsCasts:
Learn more or hide this
GitHub User: rossmc
I ran into the same issue, I posted a solution at http://stackoverflow.com/a/15865006/1814446
In the end I dropped the jQuery file upload gem soloution all together & followed Episode #196 for uploading multiple images.
I'm also having issues implementing this soulution with nested forms, has anyone found a solution to this.
I've posted for help on stack overflow http://stackoverflow.com/questions/15599613/multiple-image-uploads-in-a-nested-form-with-carrierwave