For all you who have converted k610 to w660 after long time solved problems with illumination - here you have patch and after applying patch you need to upload power_up_musicmode.ble from original k610i lighteffects to folder tpa/preset/system/lighteffect (without that in walkman no light)
Code:
;W660 R8BB001
;Turn orange lights completely off
;Now Walkman works at K610@W660 even if the backlight is at 100%
;(C) MoneyMasteR aka DoCent
453C4A2C: 01F0DAF9 C046C046
453C4A40: 01F036FA C046C046
453C4A54: 01F058FA C046C046
and here you have lighteffect