Finally I arrived to install ala-demo on a windows 7 (8gb) machine with virtualbox. I would set the focus on the mysql connection problem that I had during the Paris meeting. This problem is in fact related to the ansible version above 1.8. (Dave, Tim) If you follow the install instructions of ansible here:
the latest ansible will be installed. Which is a version above 1.8. (1.9.1 or 2.0.0) the ala-demo install dosent work with this version.
It is necessary to install ansible with:
sudo pip install ansible version===1.8.4