I'd thought of that, but it still leaves access to closing the app, & to menu items that are potentially hazardous (e.g. Save As can be used to overwrite important files) - the people running the charity are not particularly computer literate & want to feel safe from the odd malicious visitor.
Thanks for the suggestion anyway.
Mike
"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong." - Richard Feynman