Main Menu Issue

Hi,
I have created a Main Menu of my project following the tutorial https://docs.unrealengine.com/latest/INT/Engine/UMG/QuickStart/4/ on unrealengine.com website.
The issue is that as I open the preview of the project, I have to click once before “activating” the menu buttons.
The same issue is when I start the game: the mouse cursor is shown, and I have to click once to enter in the “game mode” moving around with the mouse.
Any suggestion about this issues?
Thanks a lot!

bende bu sorunun cevabını arıyorum fakat bulamıyorum

birde bende fare imlecin konumu sol en üst köşe 0,0 konumunda oluyor main menüyü açınca ve 1kez tıklayınca ekrana main menü aktif oluyor.