1) Make sure you upload the latest version of the WA_ecart/boh_PHP.php file.
2) Then open up the bracelets_aluminum.php page and edit the Add to Cart server behavior. You don't have to change any settings, just click "ok" in the server behavior once opened and it should reset the code to match the current cart.
Then upload that file and the problem should be resolved.
You will likely have to do this second step for any page that has an Add to Cart button on it. The issue is that the cart object has been updated and a column has been added or removed leaving the add to cart buttons out of sync. This process will get the code updated to work together again.