gts, I hope you see this. Many thanks for your advice. We took the front fascia of the panic button off via 2 long flat head screws. We cleaned out the fluff and dust and made sure that the red bits were perfectly mobile (no dust restricting them). Then made sure that it was in reset mode by pushing up the bit at the bottom that the key pushes up. Then reattached it and set it off and reset it and this cleared the panel. Taking things apart (especially those with a tamper mode) isn't something we would normally do but we did because of your post. thanks again.
Jenny
June 2013