Hi Bastian, Cyrille, Vaggelis,
I've solved my problem; seen that my problem has occurred because of my final transformation atom(atom0.xsl) in scenario step was not valid. I've edited the atom0 with necessary changes. It works now. Cyrille, Vaggelis, please check it, may be you have the same.
Thanks for your your consideration, Bastian.
Regards
Altan