As suggested by Corbon, I will do this question here:

17. Armour and deep water - variable armours, and armour bonuses from non-armour items (question for the next FAQ)

And, what happens if he has armour unequipped -ie. in his pack-? Can a hero put an armour in his pack, move, and reequip it later to ignore the deep water penalty?

gran_orco said:

Deep Water
It costs two movement points to enter a deep water space. In addition, heroes entering a deep water space must spend one fatigue, plus one additional fatigue for every point of armor (including both natural and worn armor , rounded down) they have. For every point of fatigue a hero cannot or will not pay, he loses one wound (ignoring armor). Figures in deep water
cannot jump.

Unequipped items do not provide the hero with anything. That includes points of armour. Therefore armour in teh pack is irrelevant for deep water. Yes, a hero can unequip his armour, move, and re-equip it later.

In the page 30 the description is slightly different:

This cost is increased by
one fatigue for every two points of armor ( natural or otherwise ,
rounded down) the hero has .

Which one is correct: one says for every point of armor, and in page 30 it is for every 2 points and armour he has.

gran_orco said:

Not "for every 2 points and armor the hero has", but "for every 2 points of armor the hero has". An armor in the hero's backpack gives him 0 armor points. The backpack is magical and floats a couple of feet above the heroes' heads (it doesn't hamper them when fighting or running either, so why should it hamper them when swimming?).

gran_orco said:

The 1 pt vs 2 pt is a known typo, corrected in the FAQ already IIRC. It is pretty obvious because both instruct you to round down, and there is no rounding if it is 1 for 1!

Otherwise both say the same. It is points of armour and un-equipped items don't give any points of armour to the hero, so they definitely do not count.

Ok, thank you. I was doing it like you say, but I wanted to be sure of it. In fact, this had been corrected in the spanish translation. I did the question because I saw it "illogical", but it is clear enough.