1) white court are humans with a "demon" in them. they need to eat food for themselves, and emotion for said demon. They are affected by red court saliva, and since they have blood, i can be drunk by the reds. However! our DM says the venom lasts 2 days for vanilla mortals, 12 hours for the supernatural, non fey.
2)12 hours. inhuman regeneration could be used to half this to 6, but it would disable the minor consequence due to it being busy. My character spent 3 hours doing pushups, essentially an endurance contest, to sweat the crap out. replaced the red saliva exposure with a mild consequence "tired". which a goodnight sleep took it out.
3)red sunlight removes their human guise, and satisfies their catch. So if you get one in the sunlight, non toughness or regeneration for them. Its like you performing operation on yourself while in a bathtub of lemon juice. It does not kill them, but it does damage black court.
Due to the stress of the catch being satisfied, the vampire must make discipline checks or get hunger stress. Thats why they can eventually be taken out in sunlight, and its why Bianca had to feed on the chick, when Dresden left her place. She had to feed her hunger due to the stress.