I've just started playing AoW II, as I've already played with the first and third game, I love this already. But I have some questions regarding the campaign and AI.

I'm on the Serpent river Water level, where there are a lot of portals. I don't understand how they work, what are the rules. The AI seems to pop up at random, ignoring the rules of only going forward with the portals, while I can't do things that the AI can. For example ignoring a 2nd portal in the line and popping up at the 3rd one, while I have to still hop onto the 2nd one to get to 3rd portal. This is very annoying, as one of the portals is in a holy storm zone, where you always get hit by a holy blast. Can you even go backwards on portals? I can't do that, it seems.

My second question is regarding the Wizard Skills. I've read somewhere that you can 'research' the Wizard Skills, like Channeler and Pacifist, to like Channeler level 5. I only see 3 skills at the start of that level and no levels. How do yo do that? Do you 'research' it by building some Wizard Tower related building in a city?

Another thing is that on this level, I'm with the humans, but still, I can't ask neutral stanced neutral units to join me (like in AoW 1). I'm currently looking at two halfling cities, and my only option is to fight them.

Is it better to concentrate on health and attack on a hero, or getting random skills? Like mountaneering or slingshot?

Oh, and how do you decide which hero to bring with you to the next campaign level? Is it random?