I'm sorry. I have a problem with the download portfolio. I don't know if is a problem inherent the theme, or only the plugin (nextGen).
But I try to ask you....
if you see this page: http://www.gdbautomotive.com/#!download-folio/
and you try to select some images....when you click on "Download selected image", an error string appear in the page.
What is that?? How can I fix this problem and use the downloader?