World Partition Data Layers: Loading and Unloading Actors Programatically

Using the Editor Utility Widget, I am trying to generate actors and then assign them to certain data layers. One of the data layers is supposed to hold unloaded actors. I am able to generate the actors and assign them to the correct data layers, but I am not able to unload the actors programatically. If I restart the editor the correct actors will be unloaded. Is there a way to unload the actors without having to close the editor?

Also, is there a way to then load specific unloaded actors?