Just found this thread. I have been experiencing a similar pattern of 1 egg (either without the shell or their is a portion of a very soft shell present) as described beneath the roost bar. This happens maybe once every 2 weeks.
I will pick up some vitamins for them. I am also curious about the worm issue. I have not given them anything for worms. Should I be? And really, the raw pumpkin seed/buttermilk concept works? How long do you soak the seeds in the buttermilk? Do you strain the seeds after soaking, before feeding them to the chickens? What quantity of seeds do you feed?