Issue on savedsearches access using custom role on a custom app

Hi, we have a Splunk Server Instance and we have developed several custom app. To limit access we are creating custom roles to limit access only to the related custom app. All is working fine apart the saved search results visualization. Every time that the custom role user try to see a saved search the result is a "Web page not found". I've already modified permission to grant the custom role on read and write, I've changed the savedsearches.conf of the custom app to work on dispatch as user and dispatch app the custom app. I've also tried to change the capabilities for the custom role but seems that the only one that fix the issue is the admin_all_objects. But assigning this capability to custom user he will see all other apps so not fine. Any suggestion? Thanks and regards Tomaso