Paperwork produces a note supporting old set-up (7)
I believe the answer is:
origami
'paperwork' is the definition.
(artworks made from paper)
'a note supporting old set-up' is the wordplay.
'note' becomes 'mi' (as in 'do re mi').
'supporting' says to put letters next to each other (in a down clue, some letters go below others).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'set up' becomes 'rig' (synonyms).
'a'+'mi'='ami'
'o'+'rig'='orig'
'ami' put after 'orig' is 'ORIGAMI'.
'produces' acts as a link.
(Other definitions for origami that I've seen before include "Oriental art of paper folding" , "Japanese paper-folding art" , "Japanese art of folding paper into decorative shapes" , "Japanese craft of paper-tearing" , "I'm a giro (anag)" .)