title: UE4: How to cast to another blueprint?
body: <p>I have a UI widget <code>elevatorButton6</code>. When player press the button on this widget, I want to launch a bluerint <code>bp_elevatorButton6</code>, but I can't cast to it</p>
  
  <p>Widget:
  <a href="https://i.stack.imgur.com/SweLq.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SweLq.jpg" alt="enter image description here"></a></p>
  
  <p>Here I use interface <code>bpi_elevatorButton</code>:
  <a href="https://i.stack.imgur.com/VeFgR.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VeFgR.jpg" alt="enter image description here"></a></p>