On my device, S2U launches every time the phone goes idle or the power button is pressed. Actually there are random exceptions, but it tends to work pretty well. Here is my reg settings.
Code:
[HKEY_CURRENT_USER\Software\A_C\Slide2Unlock]
"ShowAppointment"=dword:00000001
"DateFormat"="dddd', 'MMM dd yyyy"
"TimeFormat"="hh':'mm tt"
"Slide2UnlockPath"="\\Windows"
"ACBlankScreen"=dword:00000000
"ACOffLCD"=dword:00000000
"ACIdleStart"=dword:00000000
"BlankScreen"=dword:00000000
"OffLCD"=dword:0000003c
"IdleStart"=dword:00000001
"AutoStart"=dword:00000001
"WallpaperLandscape"="\\Windows\\GFX\\Res\\wallpaperL.bmp"
"Wallpaper"="\\Windows\\GFX\\Res\\wallpaper.bmp"
"Speed"=dword:00000003
"VGAfix"=dword:00000000
"CloseApp"=dword:00000000