Model (from GDFS):K850i
MAPP CXC article: R1FA035 prg12004400_GENERIC_SO
MAPP CXC version: R1FA035
Language Package: WESTERN-EUROPE
CDA article: 1202-0000
CDA version: segsm
Default article: 1200-5441
Default version: R1FA035
PROVIDER: 000-00
SIMLOCKS NOT DETECTED
Elapsed: 8 secs.
FILE RECOGNIZED AS CUSTOMIZATION PACKAGE.
MODEL:HB1-06 Gen
CDA: CDA102568/106
CDA REV: R5A
VARIANT:AMERICA_1
LANGUAGE: EN CF XL
SIGNED MODE (USING SERVER)
ALTERNATIVE SECURITY BYPASS ENABLED
PLEASE CONNECT PHONE IN EMP BOOTROM MODE (HOLD "2+5")
CFG:110000000000
ChipID:C802,EMP protocol:0401
BOOTROM MODE DETECTED
OTP DBG: [1,52,0,35882528658582]
OTP LOCKED:1 CID:52 PAF:0 IMEI:35882528658582 CERT:RED
LDR:2009-06-26 15:47 CXC1250843_DB31XX_CS_LOADER_ACC_SDRAM_R2A082
LDR:2009-06-26 15:48 CXC1250780_DB31XX_CS_LOADER_APP_SDRAM_R2A082
GOT SEED:AAD7A89C3400A979C561C9A0
P96 AUTH PASSED
RESTARTING ...
ChipID:C802,EMP protocol:0401
BOOTROM MODE DETECTED
OTP DBG: [1,52,0,35882528658582]
OTP LOCKED:1 CID:52 PAF:0 IMEI:35882528658582 CERT:RED
DEVICE KEY:FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF (1)
LDR:2009-06-26 15:54 CXC1250781_DB31XX_RESET_LOADER_ACC_SDRAM_R2A082
LDR:2009-06-26 15:54 CXC1250782_DB31XX_RESET_LOADER_APP_SDRAM_R2A082
GOT SEED:033E7B423400A979C561C9A0
P96 AUTH PASSED
RESETTING SECURITY TO FACTORY STATE ...
RESTARTING ...
ChipID:C802,EMP protocol:0401
BOOTROM MODE DETECTED
OTP DBG: [1,52,0,35882528658582]
OTP LOCKED:1 CID:52 PAF:0 IMEI:35882528658582 CERT:BROWN
LDR:2010-03-02 17:56 CXC1250777_DB31XX_PRODUCTION_LOADER_ACC_SDRAM_R2A0 96
LDR:2010-03-02 17:56 CXC1250778_DB31XX_PRODUCTION_LOADER_APP_SDRAM_R2A0 96
WRITING SEMCBOOT ...
PREPARING SECURITY ...
PHONE DOMAIN: "RED"
SIGNING ...
DEVICE KEY RESTORED
writing "D:\Sony Ericsson\Firmware\k850\Nueva carpeta\K850_R1FA037_FS_HUTCH-WORLD_RED52.fbn"
ALLOWED DOMAINS: BLUE BROWN RED
MAXIMUM CID: 52
Will flash 449 blocks ...
ssw file not accepted,error:6F 
Elapsed: 196 secs.
I tried with r1fa035 and r1fa037 (log) and no success. Phone doesnt swicht on, vibrate, and stuck with keypad lights on.
Thanks!