Populating Flow graph fields with objects not on the map

Looking at the VR project sample, in the boxgarden level, the flow graph scripts that generate a bunch of random boxes use an Entity:SpawnArchetype node with its Archetype set to “Level.Starter.Physics_Box_Resting”.

How do I select the object to populate this field when the object isn’t on the map? Is there some way to populate the field that doesn’t involve selecting the object?

Also, if there is a flow graph node with an entity assigned, is there any way to figure out what that entity is from looking at the flow graph? I guess I could use a debug node to output the entity ID, but is there any way to do that in the UI?