I’m not sure why the difference between the example and yours. However, just before ship we did a pass on categories and hid a bunch that didn’t seem necessary.
That said, I suspect that your problem is that you need to enable the mouse events in your player controller properties.
This may help though: I can get a click event to fire for my tree. And the tree has a 'Collision section in the details, whereas my buttons (which are copies of the Commentary_Box from the Blueprints Example Demo minus the little i symbol) and the box brush do not have these settings in the details window.
So I dont know if this is exactly what I would call a solution, but by converting brushes to Meshes (select a brush, go to details, click the down arrow under brush settings to see extended settings, and choose create static mesh) the events will now fire.
Warning converting you object to a static mesh will mess up your texture mapping. Or it did to mine anyway.
after a hole day fixing this problem i realised that , in my mobile project actor on click function dont work , if ur project is for mobile try “event begin input touch” cause player cant click at mobile device or mouse over !