This is an update to the scanlines effect I uploaded a long time ago. Mods are welcome to delete the older thread, as this one supercedes it.
This effect produces dark, smooth "scanlines". You just input the number of lines the screen will have and the width (as a coverage percent) and the intensity. Optionally you may provide an offset, so you can have the scanlines oscillate or glide or whatever. This is done as a percentage, so 0% and 100% look the same.
+ System: Always (every tick)
-> Sprite: Scanlines : Set Offset to int(Timer/5)%100
This will have the scanlines move up. It's speed will depend on the amount of scanlines you have chosen.