I'm new to pachinko and recently I've got a Bisty Fever Kung-Fu Gal machine in a good playable state, but have some question according to some issues and its game process:

1. When I turn it on after some period of time the screen and frame lights don't light up. Usually I have to press on/off switch several times for screen to show up, or it turns on when first ball enters start pocket.
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Do you have any clues how to fix that problem?

2. Also a couple of gameplay/playfield questions:
— When claws are usually triggered to open: in random time or some special occasions?
— It has a wired up gate on a left side. What does it do? I tried to figure out when a ball passes through it but didn't notice any changes.
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— On the bottom left of the screen there is a pic of two balls, didn't notice them to change ever, does it have any meaning or just for decoration?
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— Also there are two groups of small lights on a bottom: left group with 4 lights seemingly indicated how many times claws will open, but right group of two lights (O- and X-shaped) are unknown for me, what could they indicate?
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