Hi Filippo,
I think I know what your problem is now... But it no longer matters as the code you used has been scrapped.
The project's switched over to Github and I am now the only developer of the project. And I'm only getting started with the re-write of the project. So, currently there the project isn't working, but one of the forks on Github
https://github.com/mr-martian/Py2C is generating some working output, on super-simple integer only programs, if that interests you... :)
Regards,
Pradyun