Client black screen when game started

Hi! I’m following a network blueprint tutorial and I’ve got on idea what I’ve done wrong. I’ve doublechecked the video from the point it last worked.
This is the tutorial I’m following https://docs.unrealengine.com/latest/INT/Videos/PLZlv_N0_O1gYqSlbGQVKsRg6fpxWndZqZ/bjAeEDUd6Ls/index.html At the end of this video he click plays to start the game but for me nothing pop up but a black screen, like this Imgur: The magic of the Internet

I’m also very new to UE4, all help is appreciated!

Do you spawn a widget?

I believe you mean these? Imgur: The magic of the Internet Imgur: The magic of the Internet