[Plugin: FancyBox for WordPress] Problem with Settings: "Center on Scroll"

I’ve disabled “Center on Scroll” (Keep image in the center of the browser window when scrolling), and yet it still appears to be active.

Any idea what could be causing this, and how to fix it?

Cheers,
Michael

http://ww.wp.xz.cn/extend/plugins/fancybox-for-wordpress/