Have just tried araldite on suggestion of a friend. Closed door, having put thin layer of vaseline on the hole the catch should fit in to and any other bits I didn't want to stick, filled the hole where the catch had broken off with araldite (quick setting), holding the door firmly shut with sellotape. When hard, after a few minutes, opened door and it all came away from the vaseline as intended and now has a new catch molded out of araldite. Will see if it lasts! Any other ideas still welcome! (NB the little black button that cuts the power when the door is opened has had to be held 'open' with a bit of tissue paper as that bit of the door had broken aswell)
Steve, November 2009