Cold arena leads the French to screw up (7)
I believe the answer is:
crinkle
'screw up' is the definition.
'crinkle' can be an answer for 'screw' (thesaurus). I'm unsure of the 'up' bit.
'cold arena leads the french' is the wordplay.
'cold' becomes 'C' (abbreviation, eg on taps).
'arena' becomes 'rink' (I can't explain this - if you can you should believe this answer much more).
'leads' is a charade indicator (letters next to each other) (some letters go in front of others).
'the french' becomes 'le' ('the' in French).
'c'+'rink'+'le'='CRINKLE'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for crinkle that I've seen before include "Clinker (anag.)" , "Small crease or wrinkle" , "Curl" .)