kMS videos after revamp.

So different DoT from different skills display separately?

No, all of the character's DoT stacks.
(I'm not sure where the "fire/poision dot cancel each other out" came from but fire demon/meteor stacks with poison skills)

Before the chaos update: DoT did not display when a skill is spammed.
(This can be seen in 0:27 - 0:33 in the first vid)

After the chaos update: DoT is displayed despite skill spamming.