diff --git a/etemplate/inc/class.customfields_widget.inc.php b/etemplate/inc/class.customfields_widget.inc.php
index dad6cf9ff9..9d79d93de1 100644
--- a/etemplate/inc/class.customfields_widget.inc.php
+++ b/etemplate/inc/class.customfields_widget.inc.php
@@ -26,6 +26,7 @@ class customfields_widget
 {
 	var $public_functions = array(
 		'pre_process' => True,
+		'post_process' => True,
 	);
 	var $human_name = array(
 		'customfields' => 'custom fields',
@@ -112,10 +113,16 @@ class customfields_widget
 	function pre_process($form_name,&$value,&$cell,&$readonlys,&$extension_data,etemplate $tmpl)
 	{
 		list($app) = explode('.',$tmpl->name);
+		if($extension_data['app']) $app = $extension_data['app'];
 		// if we are in the etemplate editor or the app has no cf's, load the cf's from the app the tpl belongs too
-		if ($app && $app != 'stylite' && $app != $this->appname && ($this->appname == 'etemplate' || !$this->customfields || etemplate::$hooked))
+		if ($app && $app != 'stylite' && $app != $this->appname && (
+			$this->appname == 'etemplate' || !$this->customfields || etemplate::$hooked || $extension_data['app']
+		))
 		{
 			self::__construct(null,$app); 	// app changed
+
+			// Need to keep hooked app for things like nm filter changes and validation errors
+			if(etemplate::$hooked) $extension_data['app'] = $app;
 		}
 		list($type2,$use_private,$field_names) = explode(',',$cell['size'],3);
 		$fields_with_vals=array();
@@ -493,6 +500,12 @@ class customfields_widget
 		return True;	// extra Label is ok
 	}
 
+	/**
+	 * Override to pass along extension_data - doesn't happen otherwise
+	 */
+	public function post_process($name,&$value,&$extension_data,&$loop,etemplate &$tmpl,$value_in) {
+	}
+
 	/**
 	 * Read the options of a 'select' or 'radio' custom field from a file
 	 *