Not sure I can help, but we got married in Rethymno on Crete last September. All documents, FULL birth certificates, divorce papers, Passports etc had to have an Apostille mark attached this is done by our Foreign and Commonwealth Office based in MK, tells you what to do on their website. We then, not more than 3 months before the actually wedding date, had to get a Certificate of Non-impediment, a CNI, this was done at the local Registrar Office, then sent to the FCO for the Apostille. Then everything, and I mean everything, had to be translated into Greek by an approved translator, then maybe Apostille marked, although this may have been done in Crete by our Wedding Planners. Once all this had been done everything had to go the Mayor and the booking confirmed.
At the wedding we needed our passports to identify ourselves.
I think that is all covered but it took about 6 - 9 months to get everything done.
Hope that helps a bit
H