CombinedMeshLoadedCallback is the point at which a remote OvrAvatar is safe to address, in my experience. It's a public method but it doesn't evoke an EventHandler or anything like that. So I usually hack OvrAvatar with a public bool called IsInitialized that gets flipped at the end of that callback and then WaitUntil things onto it. Not the best pattern but it works.
Is there Any possibility connect standalone platform application to oculus platform application(non oculus )Create and Join Room Functionality in cross platform.