When the app is in Test Mode, the app will only show rates at checkout when you use the first name 'Bambri'.
Because Test Mode relies on the presence of 'Bambri' as a first name, this means that you won't be able to see rates in your shipping calculator/estimator while in Test Mode.
Shipping calculators don't ask for Name information. Usually they just ask for Country/State/Postal Code. Because it doesn't ask for, or send us, a First Name field, it means that Bambri isn't included, and therefore rates in Test Mode isn't triggered.
If you shipping calculator normally shows whatever rates you have configured in your Shopify Settings, then the rates from our app should appear once you switch to Live Mode.