(Optional) You can store the model’s physical properties, materials, lights, particle emitters, and audio nodes, in the .j3o file.
Use the jMonkeyEngine SceneComposer to add these properties.
this seems like it would help me with my asset troubles. But how to do it?
I open my j3o in the scene composer and I get this: then what? How to add material? Texture? 
First, I would advice you to get rid of all the blender stuff : camera and lamps. They are not used in JME.
Second, you already have 4 pointlights in your model. I don’t know how JME handles this, since lights are not part of the scene -graph.
Similarly, I would advice against it (but I’m not sure) because I would expect lights to move with your model… And this could go for weird effects in you animations if the lights do follow your object… (Some insight of gurus may be useful there)
To add new things to your model, try right-clicking on any node of the scene-graphe. You will see “add something”. That’s the way to go…
@ettavsdro: I posted a 37-minute video in your other thread about this, in addition to the manual 
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