well, i had the same problem with a w800 and i solved it.
what software and files you need:
1) FAR Manager with SEFP Plugin
2) Recovery BIN Lite v. 1.5
3) A main firmware .mbn file

What you have to do.
1) Drag the firmware into the recovery BIN Lite. it will create a file named like the main firmware but with _RECOVERY at the end.
2) Open FAR manager and conect your phone using SEFP Plugin.
3) Select MAIN
4) Drag the firmware file with _RECOVERY into the phone and flash with this.

Note: Between FS and MAIN there is a free space that it's used for patches. In normal mode this zone it is not flashed during normal flashing. after you create this recovery file, this will flash also this zone.
Note2: I'm not responsable for any damage to your phone
Note3: Sorry for my bad english