Chickens will face either direction, sleeping beak to tail or side by side. But as long as your not having cold nights, you can probably dispense with the light at night. I do have the lights on a timer so that my nights are "shorter" in order to keep egg production up, but your girls aren't laying yet. Like all animals, they have a sleep/wake cycle. By having light on 24 hours a day, you are kind of messing with that. Let them have some "dark" time to sleep better. If it gets very cold (hopefully not that bad in May!) you could consider heat lamp, but I had my girls in an uninsulated coop in below 0 degree weather with no problem, and no heat source (other than a heated waterer to keep water from freezing)