Hi - I'm not qualified to say whether or not the installation of the cavity wall insulation was at fault.
However, (before the insulation was installed,) there was no condensation in the property.
An internet search into 'condensation after cavity wall insulation has been installed' has shown that this is a very common problem and has resulted in considerable damage to the properties. In addition to this, I have asthma and spores caused by damp have resulted in a severe asthma attack. Consequently, I am not happy to risk any health issues which could occur from damp in our property.