Musical composition from fine saint struggling in a support group (8)
I believe the answer is:
fantasia
'musical composition' is the definition.
(fantasia is a kind of musical composition)
'fine saint struggling in a support group' is the wordplay.
'fine' becomes 'f' (abbreviation).
'struggling' indicates an anagram.
'in' is an insertion indicator.
'a support group' becomes 'aa' (I've seen this in other clues).
'saint' is an anagram of 'ntasi'.
'ntasi' placed inside 'aa' is 'antasia'.
'f'+'antasia'='FANTASIA'
'from' is the link.
(Other definitions for fantasia that I've seen before include "Disney film (1940)" , "Free composition; Disney film" , "Fat as Ian (anag.)" , "animated film" , "Musical composition in an improvised style" .)