Tried your demo on IE, firefox and chrome with the same results. When you make the windows smaller, the top megamenu bars ( next to the WallStore header), only click open and show the menu items for the ‘first click’. It doesn’t open when you navigate around the site and then go back to click it . Also, the megamenu items ‘categroy items, about us, customer services) dont work. Nothing is listed under these menu items (in smaller windows). (Menus work fine in full size windows only). Maybe part of the same problem, but when the megamenu bar link doesnt work, the logo doesn’t link back to the home page either.
The second problem is the form entry boxes in Login/create account forms are far too big and extend outside the fames, and don’t collapse when the windows are made smaller.
Otherwise a really nice template.