diff --git a/CRM/Mailgunny/Form/Settings.php b/CRM/Mailgunny/Form/Settings.php
index b24a001..bdb90f8 100644
--- a/CRM/Mailgunny/Form/Settings.php
+++ b/CRM/Mailgunny/Form/Settings.php
@@ -9,7 +9,8 @@ use CRM_Mailgunny_ExtensionUtil as E;
  */
 class CRM_Mailgunny_Form_Settings extends CRM_Admin_Form_Setting {
   protected $_settings = [
-    'mailgun_api_key' =>  CRM_Core_BAO_Setting::SYSTEM_PREFERENCES_NAME,
+    'mailgun_api_key' =>  'domain',
+    //'mailgun_api_key' =>  CRM_Core_BAO_Setting::SYSTEM_PREFERENCES_NAME,
   ];
   public function buildQuickForm() {
     parent::buildQuickForm();
diff --git a/CRM/Mailgunny/Page/Webhook.php b/CRM/Mailgunny/Page/Webhook.php
index 73277d2..7761952 100644
--- a/CRM/Mailgunny/Page/Webhook.php
+++ b/CRM/Mailgunny/Page/Webhook.php
@@ -53,11 +53,14 @@ class CRM_Mailgunny_Page_Webhook extends CRM_Core_Page {
   }
 
   /**
-   * Get API key from Mailgun account.
+   * Get API key for Mailgun account.
    *
    * @return string
    */
   public function getApiKey() {
+    if (defined('MAILGUN_API_KEY')) {
+      return MAILGUN_API_KEY;
+    }
     return Civi::settings()->get('mailgun_api_key');
   }
 
@@ -103,7 +106,10 @@ class CRM_Mailgunny_Page_Webhook extends CRM_Core_Page {
     // Ideally we would have access to 'X-CiviMail-Bounce' but I don't think we do.
     $bounce_params = $this->extractVerpData($event);
     if (!$bounce_params) {
-      throw new CRM_Mailgunny_WebhookRejectedException("Cannot find VERP data necessary to process bounce.");
+      // @todo Find the email and put it on hold.
+      Civi::log()->info("Mailgun Webhook: $event #noverp @todo find email and put on hold.");
+      return;
+      //throw new CRM_Mailgunny_WebhookRejectedException("Cannot find VERP data necessary to process bounce.");
     }
     $bounce_params['bounce_type_id'] = $this->getCiviBounceTypeId($type);
     $bounce_params['bounce_reason'] = ($event->{'delivery-status'}->description ?? '')
@@ -141,7 +147,7 @@ class CRM_Mailgunny_Page_Webhook extends CRM_Core_Page {
     return $verp_items;
   }
 
-  /**
+  /*
    * Get CiviCRM bounce type.
    *
    * @param string Name of bounce type, e.g. Invalid|Syntax|Spam|Relay|Quota|Loop|Inactive|Host|Dns|Away|AOL
diff --git a/mailgunny.php b/mailgunny.php
index af586fd..342d4b5 100644
--- a/mailgunny.php
+++ b/mailgunny.php
@@ -148,6 +148,9 @@ function mailgunny_civicrm_alterMailParams(&$params, $context) {
     // Copy this header to one that will be returned by Mailgun's webhook.
     $params['X-Mailgun-Variables'] = json_encode(['civimail-bounce' => $params['Return-Path']]);
   }
+  else {
+    // Probably a single email, for which we don't have any useful information to add.
+  }
   /*
  ⬦ $context = (string [10]) `flexmailer`
    ⬦ $params['X-CiviMail-Mosaico'] = (string [3]) `Yes`
diff --git a/settings/mailgunny.setting.php b/settings/mailgunny.setting.php
index c80aa74..79ba25b 100644
--- a/settings/mailgunny.setting.php
+++ b/settings/mailgunny.setting.php
@@ -6,7 +6,7 @@ return [
     'title'       => ts('Mailgun API key'),
     'description' => ts('The Mailgun API key for the sending domain'),
     'type'        => 'String',
-    'add'         => '5.8',
+    'add'         => '5.0',
     'html_type'   => 'text',
     'default'     => '',
     'is_domain'   => 1,