use these files with setool2lite :
MAIN : K770_R8BC004_MAIN_GENERIC_VI_RED52
FS : K770_R8BC004_FS_EUROPE_3_RED52
custpack : HB1-06_Gen_CDA102568_11_R8A_GENERIC_EUROPE_2
read here on how to flash and patch unlock : Flash your phone and How to apply or remove patch using SETool 2 Lite - Top Sony Forums