Basically, my problem is that since I upgraded WP-EC to the 126.96.36.199 version, the Cart Widget shows: jQuery(".cart-contents").html("0"); instead of the 'Cart Empty' text.
I rolled back to the previous WP-EC version 188.8.131.52 and now it just shows 'Loading' rather than the cart empty text.
In both cases, adding a product to the cart fixes the problem - emptying the cart shows the correct cart empty text.
Please can someone help me fix the cart? Thank you in advance for all your assistance.