The same script is working for many of other users here, so it was not a cause...
The problem meanwhile solved. It was probably caused by archive manager in Ubuntu. After I unzipped the downloaded zip file on my Son's PC with Windows, it is running correctly.
Now I will have to cope with the part which is not allowed to talk about here as the picture still not cleared.
Thank you WanWizard and andres66 for your effort.