Thank you for your feedback and to reply, yes it's only a demo.
This demo was our final year exam demo at our Game Design school. So there is some issues, no saves and other problems (cause of a lack of time of development).
Today we are no longer together at school, we work in the video game industry in separate studios. Idif is still looking for work as a level designer by the way. (If a developer ever goes through this, recruit him, he's good).