Following the book JMonkey a Practical Guide, I’ve come to realize that after creating a new J3o scene file and opening it the scene composer(and then apply the settings, I choose flat) it is completely black. I do not see the author placing lights anywhere or applying any sort of texture, his by default has the dirt texture. As well as this, a null pointer exception keeps getting thrown in the composer(though it does not crash) and it says the following:
My flat world in the terrain editor looks like this:
Thank you much in advance!