My name is Dainius and i live in Maine where the climate is murderously cold in the winter. I have lost many a chicken in the earlier days until i have learned how to keep them going through the ice and wind storms.
My chickens are free range, but they have a home base chicken coop. I have taught them how to find food on their own (if their food might be frozen or i cannot make it out to the chicken coup.)
The one problem about letting your chickens learn how to hide in, live in, and love their big yard is that they hide their eggs in huge nests in underbrush that are very hard to find. I would look around my yard and sometimes find massive nests with about 25-35 rotten and still good eggs.
One of the ways you can coax them into laying in their coop, is by putting some of their rotten eggs in their nest. And even better, leave a few good eggs in their nest and cycle through them when they lay more. Sometimes, putting an empty egg of theirs or a wooden egg also works.
Here is a video of my chickens in the fall. You can see my dog there, she actually protects them!(Because shes a German shepherd she likes to herd the chickens as if they were sheep. She just makes sure their all in a group, but shes not always on duty doing that)