You gave evidence for when you started living together, and the months after that, that entitled you to the first, temporary visa. The evidence for that time will ALSO be part of proving your 12 months together for the Residence visa.
INZ may not have returned all the evidence you sent for the first application. So you will need to tell the CO for the Residence application the details of your Temporary Work Visa application, so s/he will know where to look in the computer records to check that the evidence for those earlier times was seen and logged at the time, so s/he can tick it off as proving the first three (or however many) months of the 12 that you need to show for Residence.
As to what else you need - you need the same kind of things proving day to day living together, but proving that you carried on still living together in the same way after the work visa was granted, and are still doing so. Even after you send in the application for residence, keep collecting, because INZ usually ask for evidence covering the processing time, just before they issue the visa.