I’m really sorry to be an askhole. I’ve asked a guys with great experience in UE4 and he recommended the same as you did, Amsanity. So I think, I can mark it an answer to resolve my question. I just don’t understand that concept.
What I did, I create the separated widget “SplashScreenWidget” and placed there the name of game Text and screenshot Image. Later I attach my “MainMenuWidget” to it and from this point I can move further one level by menu, or create a modal widget for settings and so on 
I believe it can be wrong at some point, but it completely fits my small project for now
Thanks again