I agree, I don't know the CPX well enough to know if polling would be an issue.
However, if polling where a part of the issue then I would say it's likely all the radio batteries would fail and need replacing.
It's more likely the system locked up when the power was restored as PJ says.
To move forward if you feel you have a complaint ask to speak to someone at the company and explain, if this does not give you a satisfactory resolution take it up with there inspectorate if approved.
Finally take a service contract up with another company that support your system, having a system without one is only asking for grief in the long run.