>1)About the 3 differents poisondarts...
>
> a)How many rounds sleep last?

None; the sleep poison has more of a lethargy/slowing effect.

> b)What are the effects of confusion and how many rounds do
>they last?

The main effect is that when you attack or use a targeted ability, you may get the wrong target.

> c)What are the effects of acidic and how many rounds do they
>last?

Ongoing damage.

I don't remember how many ticks/hours these things last. It probably is a little random and varies by level.

>2) And about Kansetsuwasa...
>
>Somebody told me that if I land Kote before, I have a better
>chance to land Kan...

They are mistaken.

> a) I suppose it's because save vs Kan is based on dex?
> b) Is it easier to land earlier title skills ? (ex: trip
>easier to land than Kote; kote easier than Kan; etc...)

Not necessarily; different skills have different success factors, and different skills are more likely to succeed than others.

To use your examples, trip generally IS more likely to succeed than kotegaeshi IS more likely to succeed than kansetsuwaza, but that's not based on the level you get them. Mountain storm kick, for example, will tend to succeed more than kansetsuwaza even though it's later.

Kotegaeshi and kansetsuwaza, in many cases, won't be much more than a check against a fraction of your skill. Both of those skills have decent fail rates even at 100%, but they're very powerful and both have a lot of potential to completely turn the appropriate kind of fight around.

> c) What is exactly the effect of 'slow' when I crunch with
>Kan? Does it only lower the dex? does it also slow
>recuperation rate?, does it also reduce the number of attack
>per round (that would be especially good against warriors)?

Essentially, it makes it harder for them to defend themselves (parry/dodge/etc.), it makes it easier for you to defend against their attacks (same), and makes them less likely to take as many attacks. So, yeah, it's primarily of value against people who are beating you down with melee attacks.