Shipping Costs (base_price) always returns $0.00 when used with UbertCart Google Checkout Module (uc_google_checkout)

When using Google Checkout, shipping costs are always returned with $0.00. The correct Label is retunred so the logic is firing.

I'm not a hard core programmer but I seem to have isolated the issue to around line 179ish in the .module file. It never makes it into the if statement at line 182.

 //Cycle through the product basket and apply rules
    foreach ($product_type_basket as $type => $product_count) {
      //but only apply rules for products that have rules defined for them
      if (array_key_exists($type, $product_class_rules)) {
        //Cost is base price            
        $cost = $product_class_rules[$type]->base_price;
      
        //plus a multiple for every number of units (with check to avoice division by zero)
        if ($product_class_rules[$type]->base_unit > 0) {
          $units = ceil($product_count / $product_class_rules[$type]->base_unit);
        }
        if ($units > 1) {
          $cost += (($units - 1)* $product_class_rules[$type]->additional_unit_price);
        }

        $total_shipping_cost += $cost;
      }
    }

I just can't figure out why. Any help would be appreciated.