Try
this. It does this (Backlight on Battery is 4th notch from min, on Power is Full, On Battery Standy by is 2 minutes, On Power, 10 minutes, plus the power management battery tweaks):
[HKEY_CURRENT_USER\ControlPanel\BackLight]
"BatteryTimeout"=dword:00000078
"BrightNess"=dword:00000003
"ACTimeout"=dword:00000258
"OnOffBatt"=dword:00000001
"OnOffAC"=dword:00000001
"QKeyLedOnOff"=dword:00000001
"QKeyLedTimeout"=dword:0000000A
"AutoSensor"=dword:00000001
"ACBacklightOnTap"=dword:00000001
"BacklightOnTap"=dword:00000001
"OnOff"=dword:00000001
"BatteryTimeoutUnchecked"=dword:00000000
"ACTimeoutUnchecked"=dword:00000000
"ACBrightness"=dword:0000000A
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Contro l\Power]
"WakeupPowerOff"=dword:0000003C
"ExtPowerOff"=dword:00000000
"BattPowerOff"=dword:000000B4
"SystemIdleTimerResetEvent"="PowerManager/SystemIdleTimerReset"
"DisableGwesPowerOff"=dword:00000001
"ScreenPowerOff"=dword:0000003C
"SystemPriority256"=dword:000000F8
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Contro l\Power\Timeouts]
"ACSuspendTimeout"=dword:00000000
"BattSuspendTimeout"=dword:0000012C
"BatteryPoll"=dword:00001388
"BattUserIdle"=dword:00000000
"ACUserIdle"=dword:00000000
"BattResumingSuspendTimeout"=dword:0000000F
"ACResumingSuspendTimeout"=dword:0000000F
[HKEY_LOCAL_MACHINE\Comm\AsyncMac1\Parms]
"DisablePowerManagement"=dword:00000000
[HKEY_LOCAL_MACHINE\Comm\Irsir1\Parms]
"DisablePowerManagement"=dword:00000000
[HKEY_LOCAL_MACHINE\Comm\PPTP1\Parms]
"DisablePowerManagement"=dword:00000000
[HKEY_LOCAL_MACHINE\Comm\L2TP1\Parms]
"DisablePowerManagement"=dword:00000000