Test monitors have recorded observational notes and verbal feedbacks of the users; these notes have been analyzed
to understand the more critical parts of the system and, during the development, they have been used to redesign the
functionalities of the system. In particular, a search interface based on natural language queries has been dropped
from the system because users found it too difficult to be used and not providing enough additional functionalities
w.r.t. the advanced and simple search interfaces.