I'd put some boards 3-4" high on the fronts of the nests to keep the bedding and eggs inside......unless they are deeper than the 1 1/2" they appear to be
Filling the plastic eggs with sand will give them some heft which will also help them stay in the nest.
She sure does look ready!!
New layers can be quite goofy acting, they don't know what they are doing at first and can be confused and anxious, it can take up to a month or so before they get it all figured out. They may scratch around in the nests for weeks before laying. Meanwhile, eggs everywhere, some of them can be rather funky looking, soft or thin shelled, huge double yolked eggs. But it sure is fun!