Actually everybody which is new to jME should first do all the tutorials and play with and understand them. They are really really really of big help and explain a lot. At this place a big thank to those which wrote them.
I would like if we could enforce that everybody posting questions here did the tutorials before. all of them.
OK, that’s right I’m a new to JME but I observed this tutorial. I have some prepared models that I downloaded. This models had been made by using blender and they have default materials, so I don’t define new materials and I don’t know how to use blender. I just use prepared models. I don’t know where I should resolve this in JME or in blender.
First see if you can make it work with regular JME boxes like in the samples. Then when that’s working you will know it’s something to do with your model’s materials and then you can work from there. (Easiest is to load the model in the SDK, generate materials, save the model… then you can edit the generated j3m file.)