Use XS++ v3.1 and when connect click YES to update your CID52.

Can debrand your phone with lastest version:

K800_R8BF003_FS_EUROPE_5_RED52
HB1-06_Generic_CDA102568_14_R4A_GENERIC_EUROPE_5 ( or in XS++ on Customize File System select Model K800 and CDA EUROPE_5 )
K800_R8BF003_MAIN_GENERIC_WI_RED52

Do not update via SEUS, because then you have CID 53 and cann't apply patches ( etc. unlock patch or radio without headset patch ).