Widgets are drawn in the order you create them. Strings should not be bigger than the screen. A scroller is a string which scrolls. This is useful for things such as the disk usage screen, which may be very tall. The speed is how many display frames to delay between scrolling.
Positive speeds indicate frames per movement.
Negative speeds indicate movements per frame. The inside may be bigger than the actual size, so that the frame will scroll. Notifies the client of a request error. Delete a menu item. The backlight command will likely be ignored, but users can enable it if desired.