You need this 3 files:
Main : Downloads - R8BA024_RED52 - K800_R8BA024_MAIN_GENERIC_WI_RED52 - Top Sony Forums
FS : Downloads - R8BA024_RED52 - K800_R8BA024_FS_EUROPE_5_RED52 - Top Sony Forums
and Custpack : Top Sony Forums

And XS++ offer you to upgrade CID51 to CID52 - click YES and after that you can use this files,with Setool2lite you can apply unlock patch - for all of that use this tutorial General Information about Patch-Unlocking (start here if you want to unlock) - Top Sony Forums