Gameplay Tasks have builtin magic for creating nodes that spawn actors. It supports defining BeginSpawningActor and FinishSpawningActor functions and it will automatically do the appropriate thing.

AbilityTasks have a custom K2Node called K2Node_LatentGameplayTaskCall.

This implements some extra magic to automatically call functions within a certain pattern:

 * Requirements for using Begin/Finish SpawningActor functionality:
 * -Have a parameters named 'Class' in your Proxy factor function (E.g., WaitTargetdata):
 * -Have a function named BeginSpawningActor w/ the same Class parameter:
 * -This function should spawn the actor with SpawnActorDeferred and return true/false if it spawned something.:
 * -Have a function named FinishSpawningActor w/ an AActor
 * of the class you spawned
 * -This function *must* call ExecuteConstruction + PostActorConstruction

There is a list of the function names in FK2Node_LatentAbilityCallHelper

(see engine code)