Index: nice_menus.module
===================================================================
--- nice_menus.module	(revision 1)
+++ nice_menus.module	(working copy)
@@ -230,7 +230,9 @@
   drupal_add_css(drupal_get_path('module', 'nice_menus') .'/nice_menus.css');
   // Add custom CSS layout if specified.
   if ($custom = variable_get('nice_menus_custom_css', '')) {
-    drupal_add_css($custom);
+  	if ($custom != '<none>') {
+   	 drupal_add_css($custom);
+  	}
   }
   // Fall back to default layout.
   else {