Centered pop-up tutorial no new popups

Hello. Ive been working off the centered pop-up tutorial and it appears to be working fine… i have it set up on multiple buttons so when u click an image a new window pops up displaying it. it seams though that often a new window will not pop-up and the .html(with the image) will be loaded into the previous pop-up window. the code between the tutorial and my own is exactly the same. You may check out my current progress at

or download the .fla from