It took a couple of weeks but after going through a zillon tutotirals I found one very nice solution that allow a plane to cast a shadow againts a world background- in cycles.
at stackexchange "http://blender.stackexchange.com/questions/518/how-to-make-a-model-cast-shadows-onto-the-world-texture-background/26686#26686" Also I found and untilized an edgeglow node. The space craft in the scene is from blendswap, created by David Navas -file called racingspaceship, also staring my makehuamn girl-with a modifed texture- by myself.
Finally I added the lighting effects in GIMP.