Template:BoxnavProg
From Broadcast for Schools.co.uk.co.uk
Beware - all my attempts to nest Template:Boxnav have failed, because either the template parameters don't recognise the parser functions properly, or parameters get "defined" with null values and mess up the Boxnav.
Therefore the content of Template:Boxnav is included here.
If updating, remember to update equivalent templates such as Template:BoxnavSched and Template:Boxnav.