Laying out UE4 test scene in BP with Game Mode / GameState etc

I am trying to make a physics test scene which throws objects at stacks of other objects. I want to author the locations to throw from and I want to move the camera from the spawn position.

I have authored the stacks as well as the spawn locations as basic actors.

I am struggling to see how the rest fits together.

I have put public array of transforms into the level blue print thinking I could populate that with the authored spawn positions and when I got a button press, spawn the actor. However when i click on the level blue print the public variables aren’t editable in the editor. It also means I can’t populate the actor to spawn variable either to know which actor I should spawn on press.

Then I thought perhaps it was the Game state that should hold all of this? BUt then this is not something that changes during the game.

Finally I was wondering if this should go into a Playercontroller? Then again I can’t wire the spawn positions to the player controller because it’s not in the scene.

So then that took me back to the Level blue print and perhaps I should have that find the spawn actors by tag, on start up?

This seems very simple and I’m just not very sure how I should lay it all out.

In the end.

Ball to be thrown is a Pawn. It finds the start positions in the scene.

Game Mode is basic game mode that does nothing but by having one you can change camera controller etc.

Once you have a camera controller it selects the camera actor placed in the world.

Pawn takes control input and teleports left & right, along the start positions, before being thrown into the world.