Another newbie with questions

[Vynd]

My copy of the game arrived yesterday and I had a lot of fun playing around with it Last night. But of course I also ran into some things I couldn't figure out...

1) Can I capture provinces through dominion alone? In other words, if my rating gets high enough will they just join my nation? Or is military conquest the only way to take territory?

2) The manual says that Water mages can travel underwater, and take some troops with them. How do I determine how many a given Water mage can "carry"?

3) How do I tell if a creature is Magic and requires a special commander? I'm playing as Pythium and I thought the Hydras might be magic until I tested it out.

4) How do I view and/or alter the victory conditions for a game?

Thanks in advance!