Mike. To remove broken key line it up perfectly vertically and insert a spare key into the other side of the barrel. This will push the broken piece out enough to grab with long nose pliers. Then insert spare key into barrel from the inside of the property and turn to appx. 5past/25to position, remove locating screw (in lock strip) and withdraw eurobarrel. Good luck with the ROTO system - its pretty old now.
kev, January 2007