Is the ranged attack of the catapult etc. a plain 3 attack or does it also get the double damage and (-1) modifier?
The cannon can make an attack one territory away with an attack strength of 4 (not 4-1). The Ballista and Catapult make ranged attacks one territory away at 3.
In siege vs siege, would the defending siege weapon at least get to fire back? (If not fire while the moving army sets up it's siege weapons?)
Yes defending units would get their return fire as normal, however as it states in the rules on siege units, "There are no attack-backs for units killed by a ranged attack." So it is true in all cases, except when making taking a casualty from a ranged attack.
Can a captured city be used for income/ placing units?
On page 8 of the rules it states,"A player may not place any unit
in a city that is occupied by an enemy or one whose territory is under the control of an enemy. A player may not build their own units in an enemy city that they have captured."
Does a captured tomb still fear units attempting to enter? (regardless of the answer to the above question)
Good question and one I will add to FAQ along with your first question.
The tomb at this point is no long funtioning under the control of the Undead. They cannot place any units there, they have no power there. So the Dreadstone would no longer be in affect. The rules do state that they face a fear spell before when they enter the tomb before they attack. We could deduct that since they are not attacking that this isn't in affect, but I agree it needs more clarity.
Can the heal spell be used to prevent lethal damage? I.e. can it heal a single damage on a unit with only one hp as it is received to prevent destruction, or prevent a 2 damage attack from killing a hero with 2 up?
Spells are cast on the player's combat round with the exception of "Guide Fate" which specifically allows you to reroll an attack or defense. If you were to cast Heal on your combat round, but your hero already suffered a fatal hit of 2 damage then you cannot save him or her.
Does a unit with speed >1 capture territories it moves through?
No, you must occupy the territory at the end of the turn to conquer it.
Thanks for a great game!
Thank you! I'm glad you enjoy it. Please give us an after action report of one of your first games if you feel up to it.