I had taken a look at the codes.
Yes, something is wrong.
In the class t4pTemplateWoo ( found in woo-config.php ), there is no method ‘shop_breadcrumb’, this means in the written class t4pTemplateWoo, there is no function shop_breadcrumb.
I don’t know if the function is removed intentionally or it was never written, no idea what’s that for….
I will report this issue to our developers.
I had logged into your website and commented out this “redundant” code.
No error message now, and your shopping cart is working properly.