question: leaky armor leaky shields, newtonian propulsion

[Ragnarok-X]

Hi everyone, please explain to me what leaky armor and leaky shields mean.

I guess leaky armor is a component which average size and more than average damage resistance BUT without the armor abilty. This would mean there is always a chance to hit "normal" components and sometimes the "armor".

But what does leaky shields mean, or rather HOW does it work ?

The same goes for quasi newtonian engines, how do you set those components up ?

ty.