This might help
#2 HKCU\ControlPanel\Backlight\QKeyLedTimeout 30 (Reset- it may or may not work) or
Advaced Configuratio tool 3.2.
Under Input\Keyboard backlight timeout: default 10 sec (Reset- may or may not work)
or
NueROM's nueKBLight
http://www.nuerom.com/BlogEngine/page/nueKBLight.aspx (some reporting it works)
#3
http://forum.xda-developers.com/showthread.php?t=488991 (this works on my TP)
Hope it helps Tim