On the photogallery tutorial

so im making a photogallery right, and ive been through the entire tutorial inside and out. In fact even if i copy the tutorial this happens. as soon as i change the image locations in the xml file i get this:

not what i want

its like it gets stuck loading the image in or something and can only count backwards the number of times you click forward.

i know the image locations are right because i access them all the time.

any ideas?

here is the tutorial i am referencing

gracias