As promised, here is a short explanation of the bonus feature of the Nishijin Lucky Welcome arrangeball.
The bonus feature is located at the top of the playfield and starts when the first winning combination is achieved on the main card. You only get one bonus feature per game.
The bonus feature consists of 8 panels that are lit in sequence rapidly, like a really fast light chaser that goes from left to right.
This panel spots 1 and 6 OR 1, 4, 13 and 16 OR 7 and 11