I dont think so because i will remove ```$app['registration-manager']->isRegistrationEnabled()``` as it does not belong to the manipulator. Are you ok for somethink like that : 
```php

$app['registration.enabled'] = $app->share(function (Application $app) {
   foreach ($app['phrasea.appbox']->get_databoxes() as $databox) {
     foreach($databox->get_collections() as $collection) {
         if ($collection->isRegistrable()) {
            return true;
         }
     }
     return false;
   }
});

```