Double Damage

How is damage doubled in Acks? Are mods doubled?
Pc has a +1 str mod and a +1 weapon and a +2 Fighter bonus. Normal damage is 1d6+4
He is enlarged or has giant str or something.
Does he do:

p. 104, Double Damage: “Whenever damage is doubled (from backstabbing or charging, for instance), multiply the standard damage roll by two. Bonuses to the damage roll, such as from magic or strength adjustments, are not doubled.”

Been thinking about this a bit.

How is multiple doubling dealt with? Say someone with Ambush or Backstab and Weapon Focus, or Giant’s Strength, or all of the above?

Is a ‘multiple’ really just another way of saying a bonus die?

i use the 3x way: for multiple multiples:

When two or more multipliers apply combine them into a single multiple, with each extra multiple adding 1 less than its value to the first multiple

Examples: a double doubled is a triple because 2 + (2-1) = 3 or a double tripled is a quaduple becaue 2 + (3-1) = 4

Yeah in place of something official that’s what I’d do.

I just do x2 x2 = x4, and x2 x2 x2 = x8.

The worst that can happen … is pretty close to the damage a wizard does with a fireball, once or twice per day, to a much larger group of people.

The offiical ACKS rule is that each "doubling" of damage increases the damage dice by one factor. (This is exactly the same rule as in 3.5).