diff --git a/client/dist/js/GridField.js b/client/dist/js/GridField.js
index 26d9814..874a6ae 100644
--- a/client/dist/js/GridField.js
+++ b/client/dist/js/GridField.js
@@ -1 +1 @@
-!function(){"use strict";var e={669:function(e){e.exports=jQuery}},t={};var i=function i(r){var d=t[r];if(void 0!==d)return d.exports;var n=t[r]={exports:{}};return e[r](n,n.exports,i),n.exports}(669);i.entwine("ss",(e=>{e(".ss-gridfield .field .gridfield-dropdown").entwine({onchange(){const e=this.getGridField(),t=e.getState().GridFieldSiteTreeAddNewButton;t.pageType=this.val(),e.setState("GridFieldSiteTreeAddNewButton",t)}})}))}();
\ No newline at end of file
+!function(){"use strict";var e={669:function(e){e.exports=jQuery}},t={};var r=function r(i){var d=t[i];if(void 0!==d)return d.exports;var n=t[i]={exports:{}};return e[i](n,n.exports,r),n.exports}(669);r.entwine("ss",(e=>{e(".ss-gridfield .field .gridfield-dropdown").entwine({onchange(){const e=this.getGridField(),t=e.getState().GridFieldSiteTreeAddNewButton;t.recordType=this.val(),e.setState("GridFieldSiteTreeAddNewButton",t)}})}))}();
\ No newline at end of file
diff --git a/client/src/js/GridField.js b/client/src/js/GridField.js
index 9fcf113..d0f1c1d 100644
--- a/client/src/js/GridField.js
+++ b/client/src/js/GridField.js
@@ -8,7 +8,7 @@
         const gridField = this.getGridField();
         const state = gridField.getState().GridFieldSiteTreeAddNewButton;
 
-        state.pageType = this.val();
+        state.recordType = this.val();
         gridField.setState('GridFieldSiteTreeAddNewButton', state);
       }
     });
diff --git a/src/Forms/GridFieldSiteTreeAddNewButton.php b/src/Forms/GridFieldSiteTreeAddNewButton.php
index f54e97f..9586c32 100644
--- a/src/Forms/GridFieldSiteTreeAddNewButton.php
+++ b/src/Forms/GridFieldSiteTreeAddNewButton.php
@@ -2,10 +2,11 @@
 
 namespace SilverStripe\Lumberjack\Forms;
 
-use SilverStripe\CMS\Controllers\CMSPageAddController;
+use SilverStripe\CMS\Controllers\CMSMain;
 use SilverStripe\CMS\Model\SiteTree;
 use SilverStripe\Control\Controller;
 use SilverStripe\Control\HTTPResponse;
+use SilverStripe\Core\ClassInfo;
 use SilverStripe\Core\Config\Config;
 use SilverStripe\Core\Injector\Injector;
 use SilverStripe\Forms\DropdownField;
@@ -42,7 +43,8 @@ public function getAllowedChildren(?SiteTree $parent = null)
             return array();
         }
 
-        $nonHiddenPageTypes = SiteTree::page_type_classes();
+        $nonHiddenPageTypes = ClassInfo::getValidSubClasses(SiteTree::class);
+        SiteTree::singleton()->updateAllowedSubClasses($nonHiddenPageTypes);
         $allowedChildren = $parent->allowedChildren();
         $children = array();
         foreach ($allowedChildren as $class) {
@@ -66,22 +68,22 @@ public function getHTMLFragments($gridField)
     {
         $state = $gridField->State->GridFieldSiteTreeAddNewButton;
 
-        $parent = SiteTree::get()->byId(Controller::curr()->currentPageID());
+        $parent = SiteTree::get()->byId(Controller::curr()->currentRecordID());
 
         if ($parent) {
-            $state->currentPageID = $parent->ID;
+            $state->currentRecordID = $parent->ID;
         }
 
         $children = $this->getAllowedChildren($parent);
         if (empty($children)) {
             return array();
         } elseif (count($children ?? []) > 1) {
-            $pageTypes = DropdownField::create('PageType', 'Page Type', $children, $parent->defaultChild());
+            $pageTypes = DropdownField::create('RecordType', 'Page Type', $children, $parent->defaultChild());
             $pageTypes
                 ->setFieldHolderTemplate(__CLASS__ . '_holder')
                 ->addExtraClass('gridfield-dropdown no-change-track');
 
-            $state->pageType = $parent->defaultChild();
+            $state->RecordType = $parent->defaultChild();
 
             if (!$this->buttonName) {
                 $this->buttonName = _t(
@@ -92,9 +94,9 @@ public function getHTMLFragments($gridField)
             }
         } else {
             $keys = array_keys($children ?? []);
-            $pageTypes = HiddenField::create('PageType', 'Page Type', $keys[0]);
+            $pageTypes = HiddenField::create('RecordType', 'Page Type', $keys[0]);
 
-            $state->pageType = $keys[0];
+            $state->recordType = $keys[0];
 
             if (!$this->buttonName) {
                 $this->buttonName = _t(
@@ -131,7 +133,7 @@ public function getActions($gridField)
     }
 
     /**
-     * Handles the add action, but only acts as a wrapper for {@link CMSPageAddController::doAdd()}
+     * Handles the add action, but only acts as a wrapper for CMSMain
      *
      * @param GridField $gridField
      * @param string $actionName
@@ -147,20 +149,20 @@ public function handleAction(GridField $gridField, $actionName, $arguments, $dat
             $tmpData = $tmpData['GridFieldSiteTreeAddNewButton'];
 
             $data = array(
-                'ParentID' => $tmpData['currentPageID'],
-                'PageType' => $tmpData['pageType']
+                'ParentID' => $tmpData['currentRecordID'],
+                'RecordType' => $tmpData['recordType']
             );
 
-            $controller = Injector::inst()->create(CMSPageAddController::class);
+            $controller = Injector::inst()->create(CMSMain::class);
+            $form = $controller->AddForm();
 
-            // pass current request to newly created controller
+            // pass current request down in case either of these needs it
             $request = Controller::curr()->getRequest();
             $controller->setRequest($request);
+            $form->getRequestHandler()->setRequest($request);
 
-            $form = $controller->AddForm();
             $form->loadDataFrom($data);
-
-            return $controller->doAdd($data, $form);
+            return $form->doAdd($data, $form);
         }
 
         return null;
diff --git a/src/Forms/GridFieldSiteTreeEditButton.php b/src/Forms/GridFieldSiteTreeEditButton.php
index c11c608..f6e0754 100644
--- a/src/Forms/GridFieldSiteTreeEditButton.php
+++ b/src/Forms/GridFieldSiteTreeEditButton.php
@@ -28,7 +28,7 @@ public function getColumnContent($gridField, $record, $columnName)
         // which can make the form readonly if no edit permissions are available.
 
         $data = ArrayData::create([
-            'Link' => $record->CMSEditLink(),
+            'Link' => $record->getCMSEditLink(),
             'ExtraClass' => $this->getExtraClass(),
         ]);
 
diff --git a/src/Model/Lumberjack.php b/src/Model/Lumberjack.php
index af44f75..0553604 100644
--- a/src/Model/Lumberjack.php
+++ b/src/Model/Lumberjack.php
@@ -28,7 +28,7 @@
  *
  * @author Michael Strong <mstrong@silverstripe.org>
  *
- * @extends SiteTreeExtension<SiteTree&static>
+ * @extends Extension<SiteTree&static>
  */
 class Lumberjack extends Extension
 {
diff --git a/yarn.lock b/yarn.lock
index 16cbd7a..2b5ebec 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2172,9 +2172,9 @@ cosmiconfig@^9.0.0:
     parse-json "^5.2.0"
 
 cross-spawn@^7.0.2, cross-spawn@^7.0.3:
-  version "7.0.5"
-  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-7.0.5.tgz#910aac880ff5243da96b728bc6521a5f6c2f2f82"
-  integrity sha512-ZVJrKKYunU38/76t0RMOulHOnUcbU9GbpWKAOZ0mhjr7CX6FVrH+4FrAapSOekrgFQ3f/8gwMEuIft0aKq6Hug==
+  version "7.0.6"
+  resolved "https://registry.yarnpkg.com/cross-spawn/-/cross-spawn-7.0.6.tgz#8a58fe78f00dcd70c370451759dfbfaf03e8ee9f"
+  integrity sha512-uV2QOWP2nWzsy2aMp8aRibhi9dlzF5Hgh5SHaB9OiTGEyDTiJJyx0uy51QXdyWbtAHNua4XJzUKca3OzKUd3vA==
   dependencies:
     path-key "^3.1.0"
     shebang-command "^2.0.0"