I am using your plugin on a site that also uses a lightbox plugin in conjunction with the standard WordPress photo gallery.
When viewing the site at full-width (i.e. your menu is hidden via CSS), after you click on a photo and have it come up in the lightbox, your menu then displays. I suppose it has to do with the lightbox width being smaller than the maximum width for your menu...the original image widths are 600 and my breakpoint for your plugin is 768. Is there any way to prevent this?