Embedded is just the name of my widget, your widget is called Projector Widget. Also, you cannot cast while dragging Execution wires (the white ones), use the data wires, they are context sensitive and will give you a sensible range of choices.
You’re trying to cast to a widget (ProjectorWidget), cast to a widget component instead (Projector).
Take a closer look at the image I posted, especially at the comments. It seems you’re not following it right. You’re trying to cast by dragging the white wire while you should be Getting User Widget Object first.
One note, this will not work in the Construction Script.