I've just submitted v2.4.1 for the Zen Cart moderators' review.

This release contains changes associated with the following GitHub issues:

#123: Correcting login page layout when the 'PayPal' block is not the first.
#325: Correct PHP Warning when a shipping module reports errors.
#326: Session messages were 'lost' during the checkout_one_confirmation page's processing.
#327: Logged-in customers' ship-to address set by the shipping-estimator weren't being used.
#328: Correcting PHP warnings due to var_export complaining about circular references.
#329: Use JSON.parse instead of the (deprecated) jQuery.parseJSON; correct HTML validation issues.
#330: Use zen_country_zones to gather any country-specific 'zones'.