Unity3D in a native iOS application woes

So I have been at this an age and although I find lots of talk I have not found the answer?

I can load Unity from a native IOS app IF I create the view controller and view via code, but this is not what I need.

I need to create my UI from a storyboard that has the initial view controller being a navigation controller and try as I might I cannot get the app to start from the navigation controller

Any pointers please?

Thanks