1. Does the loss of double defense by the defender on the Betrayal card occur for a single round or both rounds of a Storming Attack?

Both rounds

2. Can a unit move directly from the hex that is the source of the Haliacmon River to the hex that is the source of the Arathus River?

Yes, but you must stop in that hex.

3. Rule 2.14 implies that reinforcements only occur at Major Cities while section 8 allows existing blocks to take reinforcements or new Reserve blocks to be placed at Minor Cities. Which is correct?

This is an inconsistency. 1 BP is allowed in a minor city. Rule 2.14 will be changed.

4. According to Rule 1.5, if a player moves a ground block into a Strait hex with an enemy ship, the ground block loses 1 step and retreats (back to hex it came from according to the Retreat rule). What’s the point of ever making such a move? This also seems to contradict the Straits example in the sidebar on page 3.

This effect applies only if the move requires the strait was crossed to reach the town. If not, the strait rule doesn’t apply at all. Players sometime blunder into a navy but will learn that crossing a strait into unknown forces is risky.

5. Suppose there is an enemy block on the Naupactus hex. It would seem that a player could move two blocks from the Pleuron hex into the Naupactus hex if the enemy block was considered to be on the Naupactus side of the strait but only a single block if the enemy block was on the Peloponnese side of the strait. Which is correct?

The hex that the unit is coming from establishes whether the move involves crossing a strait to reach the town or not. For Naupauctus, a move from Pleuron or Delphi does not cross the strait while a move from Patrae or Sicyon does. The location of the town is the key. The Naupactus defenders are deemed to be where the town is.