Adding Toggling in Level Blueprint (4.9.1)

I’m trying this, but in 4.9, PointLight1 is in Blueprint_CellingLight.
So I dragged Bluepoint_CellingLight into Level BluePrint Editor and connected to Toggle Visibility,
but it doesn’t work. When I checked “Propagate to Children”, it works but all part of lamp disappearing.

How can I do this?

First of all this is a very early tutorial. You should pretty much never use the level blueprint for changing lights except it’s a scripted scene. Or in other words. Unless you know exactly why you use the level BP and the answer is not “It’s simple right now” or “That’s how it’s done in the tutorial” you probably shouldn’t use it. But other ways require quite a lot more knowledge which is why they show it like this.

The reason this happens is that you have a full blueprint. Inside of this blueprint are multiple components one being the light, one being the static mesh (the model of the lamp) and most likely a scene component as well. You want to toggle the visibility of the light which is part of the Blueprint. The best way to do this is if you create a new function in your blueprint, drag out your light and call toggle visibility there.

Then from the level BP you can just call this function and it will do exactly what you want.