[Plugin: NextGEN Scroll Gallery] Horizontal Scrollbar disappears

Hello, When the page first loads the scroll bar is visible but after the page has finished loading the scroll bar disappears. I have tried to display it as you advised in a previous post using:

.scrollgallery .thumbarea{
overflow-x:auto !important;
}

And I have even tried using scroll instead of auto but it still doesnt work

.scrollgallery .thumbarea{
overflow-x:scroll !important;
}

Any suggestions would be greatly appreciated

Thanks

http://ww.wp.xz.cn/extend/plugins/nextgen-scrollgallery/