After a power outage of several hours, the whole controller screen is flashing, and non of the buttons do anything. Powering of and on again makes no difference. What can we do?

See How To Reset Blocks or Hailing Master on your Networker controller? - YouTube (http://www.youtube.com/watch?v=d2GyfsTJLZo)
Brivis service know about it when you get through the phone queue, but it is not linked from their web site.