Video Gallery thumbnails not showing.

Hi there,

up until 2 days ago, my website was working fine, but then the thumbnails for my videos stopped showing up. I have been in contact with the plug-in developers and they have replied with the following:

“Dear user we found out: there are some problems with your theme front-end, tour plugin can find thumbnails in admin page, but your front-end can not find them. (You can check that by changing your theme)
So please contact your theme support and ask to fix.”

Can you please look into this for me as my videos are a crucial part of my website and i need the associated thumbnails to show up on the embedded video.

my web site is http://www.jamesvanvliet.co.uk

Thanks

James