Transparent window

Hi, I am trying to make a transparent window, so the objects in the scene will display on top of windows. Take a look at this: https://www.reddit.com/r/unrealengine/comments/8e8bib/question_fully_transparentclickthru_application/
This is how it looks if I use that code:


Anyone know how to fix this? Thankyou

you can see this video

link:

The node in the blueprint was not found