Showtime Slideshow– "XML could not be loaded."

That’s what keeps showing up in the lower left corner of the slideshow instead of my images. Someone else posted awhile back with the exact same problem. He resolved it by changing the permissions, but I don’t know how to do that. Could anyone help? I’m using the Atahualpa Theme. Here’s my url: http://bobsweldart.com/wordpress/bio/process/