Getting the popup

Please contact the store owner; some required elements of this page are missing.

Looks like
zcLog2Console('Missing '+ottotalSelector);
is firing in includes/modules/pages/checkout_one/jquery.checkout_one.js

The console says
Missing #ottotal > div:first-child

Zen Cart 1.5.7d, Bootstrap template (latest - 3.2.0), One Page Checkout (latest - 2.3.10).