Hi Anne
Im not running any mods apart from your template and UK basic mail which just adds files to the shipping module so it can't be an issue regarding other mods.
Website is
http://www.thegreatgiftshop.co.uk ( its the links in the footer, all product/featured that are throwing the error)
One thought I did have which was when trying a couple of your templates, I did upload the .sql file from the all business to the database. Ive seen somewhere Sheffield blue should have its own .sql patch but its not included in the .zip file provided in the downloads section of this website.
I guess this might be the issue? if so where can i get the proper .sql file from.
Just to reiterate, everything works fine when i switch back to classic template.
Kind regards.
John