For any Dainese zip and/or stitching repairs, warranty or otherwise, they will end up at Nine Lives in Farnborough in a small industrial unit behind Infinity.
I had the two 'bib' zips replaced by them on my Bora suit last month. Back in a week and excellent workmanship; here are the details;
Nine Lives
Tel: 01252 523232
13b Morris Rd,
Farnborough
Hants
GU14 6HJ