MyBB Hacks

I've recently attempted to implement the gallery feature into a forum but it appears that when ever you upload an image via the attachment feature this is all that shows:
http://prntscr.com/fzvo5p

I follow it step by step and doesn't appear to work, currently using the latest MyBB 1.8 installment.

I think there is some problem with the link to image, with Ctrl + Shift + C (on Chrome) try to check on that image and see wha't the path of the image