Popup close button not working

I've created a popup but there's an issue with the close button - not only is out of place (the entire div its in is about 20px too high?) but the button itself doesn't close the popup.

Obviously I've switched it off for now, but I need to activate it asap. I presume there's a conflict somewhere (my theme is Enfold) but I'd imagine you may find the issue quicker than me!

Not sure if its connected, but I also tried the 'slide in' plugin, but that didn't show up at all!

I've granted you access so you can take a look.....