When using a delegate variable as a function parameter, dragging off of the delegate pin of an associated function BP node to create a custom event will create a default custom event without the input pin for the delegate variable.
1. Open Code based project
2. Add code to project based on Actor (MyActor)
3. In header file add the following:
a. above the UCLASS() macro:
b. Inside the class body:
5. Create a blueprint based on MyActor (MyActorBP)
6. Add call to Initialize function in the Event Graph
7. Drag off of the red On Initialized pin of the function node
8. Create a custom event
Basic Custom event node is created with only an execution pin
FOnInitialized Event node would be created with a boolean input pin
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-16352 in the post.