Multipliers become slightly more difficult to light each time; i.e. it requires a few more bumper hits per gear. I see many people cashing out their multipliers as soon as they drain; don't do that! (The multiplier doesn't apply to bonus either.)

In multiball I believe you hit every shot twice for regular Jackpots. Hitting all of them will light super jackpots.

Nope, you only have to hit each shot once. Base jackpot value goes up the more races you have won. Supers award 3X, 4X, then 5X.

Getting to the challenge wizard mode is easy but the race modes wizard mode is much harder to get to. I have yet to reach that one and red mist multiball.

World Championship is hard to reach, but doable if you focus on it and has a good payoff. Final Challenge is indeed easier, but the payoff is usually lower. You'll need to collect a few trophies to get the jackpot values up to decent points.

Yes, I wrote the majority of the game code, based on the main ideas from the core development team in the UK.

Mostly I'm just coding what I'm asked to, and giving feedback on what I think works/doesn't work for them to decide.