  We discuss a number of essential dynamical features of the Biroli-Mezard
model. We observe a dynamical slowing down which for high densities depends
both on the observation time and on the age of the system. We relate this
ageing behavior to the real space dynamics of the system, from which it is
clear that the system initially gains mobility due to some essential initial
restructuring. We discuss crystallization, its relevant time scales and
connection with ageing. We quantify how heterogeneous the slow dynamics of the
BM model is by investigating the dynamical susceptibility and discussing its
dependence on the age of the system. We establish a number of quantitative
evidences that are in good agreement with a recent analysis.
