It is possible to use custom WooCommerce order statuses for triggering review reminders. Custom order statuses can be selected from the dropdown field 'Order Status' on 'Review Reminder' tab in the plugin's settings. The dropdown field shows only 'paid' order statuses. If an order status is not marked as 'paid', it will not be shown in the dropdown.

The plugin uses the standard WooCommerce function wc_get_is_paid_statuses to obtain a list of 'paid' order statuses.

If some custom order status is not shown in the dropdown, please make sure that it is created as a 'paid' status. Here is a code snippet illustrating how to mark and a custom order status as paid:

add_filter( 'woocommerce_order_is_paid_statuses', 'my_custom_woocommerce_order_is_paid_statuses' );

function my_custom_woocommerce_order_is_paid_statuses( $statuses ) {
  // already included statuses are processing and completed
  $statuses[] = 'my-custom-status';
  $statuses[] = 'my-other-custom-status';
  return $statuses;
}