LinDA Analytics Engine - Download report doesn't work

[smouzakitis]

I followed the tool examples / steps for Example 1 : How to prepare and interpret an analysis. After step 15 "Press submit and wait." , i saw the results and clicked Download report.
I got the following:

OSError at /analytics/report/58/exportreport/

wkhtmltopdf exited with non-zero code 2. error:

                    response = wrapped_callback(request, *callback_args, **callback_kwargs)

 ...

▶ Local vars
/home/linda/LindaWorkbench/linda/analytics/views.py in exportreport

        pdfkit.from_url('http://localhost:8000'+str(pdfurl), tempfile)

 ...

▶ Local vars
/home/linda/LindaWorkbench/LindaEnv/lib/python3.4/site-packages/pdfkit/api.py in from_url

    return r.to_pdf(output_path)

 ...

▶ Local vars
/home/linda/LindaWorkbench/LindaEnv/lib/python3.4/site-packages/pdfkit/pdfkit.py in to_pdf

            raise IOError("wkhtmltopdf exited with non-zero code {0}. error:\n{1}".format(exit_code, stderr.decode("utf-8")))