Q: Why do some ranged weapons have these qualities if the text about the "Divided Attack" indicates that it can only be made with the Fight Ability?
The Myrish Crossbow (Table 9-3: Weapons; P 157) has the Fast Quality. The Light Crossbow has the Slow Quality.
A Fast weapon is designed to slip past your opponent’s defenses and enable its wielder to strike rapidly. When you make a divided attack using a Fast weapon, you gain +1B on each test. Bonus Dice gained from the Fast quality can exceed the normal limits.
A Slow weapon is cumbersome and difficult to wield with speed and grace. You may not make Divided Attacks using these weapons.