I first tried what is proposed in answer 10 of Help trying to install Plone without Vagrant on Ubuntu 16.04
Used instead of develop.cfg the buildout.cfg
I had to do some more manual "pip install ..." taking into account, that we need the SSL index option: --index:https://pypi.python.org/simple/
After that, it worked.
Other proposal: Start the whole training manual again. In between there seemed to be something wrong during installation and purge processes for nodejs and npm.
Hope it is helpful for anyone working with Ubuntu 12.02
Regards, FL