I have a basic programme on excel for doing the rota's at work but it is now
not upto the job, I have several different staff working a number of
different shift patterns, does anyone know of a programme, or some formulas
that can cope with the following:-

4 days on , 4 days off
4 days on, 3 days off
4 nights, 3 days off
1/2 day on, 3 days on, set days
and so on