The cart is bugged, if you add one product others get added too. e.g add the bear, and two get added.
http://demos.xcartmods.co.uk/ability444/product.php?productid=89&cat=248&bestseller=Y
Phil are you on Skype? I'll be looking through the template for the next hour or so to try and find bugs. Would be easier to tell you them via Skype instead of spamming this thread.
*Edit* Odd seems fixed now, how strange.