I received an answer from the team . In my case is easy. I share it with you. It appears that in not able to export to blender, just to Maya. i still need to check that info out but now the app is generatig the characters.
To be able to see your metahuman navigate to the account icon sing in within the window.
Ok. Now I am going with the Maya step.
I hope you find this info useful. 
PSS: Since I am new I can only upload a photo, so I made a collage.