Hello ,
I tested this by putting together a barebones project and I’m not seeing any issues with this node in 4.15.1. I set up this widget and created/added it to the viewport on BeginPlay:
Pressing down on the D-pad of an Xbox 360 controller triggered the print. It would sometimes not occur due to this being on tick with a delay but that was rare. Is there any reason you’re doing this on tick instead of overriding the OnKeyDown event?
Have you tried debugging your blueprint to ensure that this is where the execution is failing to continue?