Since you are using the layout custom field, you should probably also take a look at this post…
php-input-variables-exceeded-1000
On complex field groups it is possible for the number of form variables submitted to exceed your web server’s maximum number of allowed variables per post. This happened to me on what seemed like a field group that wasn’t all that big. But once you start repeating layouts, the number of inputs can become quite large.
Until the developers start using a different method of saving data (like I suggested in my post) you will either have to change the configuration of your web server (not always possible on shared web hosting) or figure out a different way to do it.
