Arrangement of this music could leave creator hanging (9,5)
I believe the answer is:
gregorian chant
'arrangement of this music' is the definition.
'Gregorian chant' can be an answer for 'music' (Gregorian chant is an example). I'm not sure about the 'arrangement of this' bit.
'leave creator hanging' is the wordplay.
'creator hanging' can be anagrammed to 'GREGORIAN CHANT'.
Though, I'm not sure how this is indicated.
'could' is the link.
(Other definitions for gregorian chant that I've seen before include "Medieval plainsong" , "variety of plainsong" .)