How do drones deal with Orion stealth? Do they not fire and remain available, like photons? Do they fire and waste a drone from your ammo? Or do they fire and resolve their roll against stealth upon "impact" when they make their attack?

As for plasma, I assume the rule for "slow" weapons applies, buy what about the PP you must spend? Do you lose them, or do you not apply them until after the stealth roll? Come to think of it, this applies to overloaded photons as well.