MAIN firmware: W660_R8BB001_MAIN_GENERIC_FY_RED52.mbn
FS(file system) firmware: W660_R8BB001_FS_MEDITERR_RED52.fbn
custom pack: a zip package what contain the tpa folder etc.(DO NOT unzip it)
Flash your phone selecting these files...

You need to unlock the phone again, because the "unlock" patch is gone due to MAIN reflashing.