Criticise German in crumbling paradise (9)
I believe the answer is:
disparage
'criticise' is the definition.
(disparaging is a kind of criticising)
'german in crumbling paradise' is the wordplay.
'german' becomes 'g' (abbreviation).
'in' means one lot of letters goes inside another.
'crumbling' indicates anagramming the letters.
'paradise' is an anagram of 'disparae'.
'g' inserted into 'disparae' is 'DISPARAGE'.
(Other definitions for disparage that I've seen before include "Belittled" , "I grasped a change to belittle" , "Slight" , "Scorn" , "Run down" .)