Clone
_form.html.erb
<%= form.text_field :label %>
<%= form.file_field :file, :multiple => @file.new_record? %>

<% unless @file.new_record? %>
  <%= form.simple_field t('.current_file'), nil do %>
    <%= link_to @file.file.url, @file.file.url, :target => '_blank' %>
  <% end %>
<% end %>

<%= form.text_area :description %>

<%= render :partial => 'cms_admin/categories/form', :object => form %>

<%= form.simple_field nil, nil, :class => 'submit_element' do %>
  <%= form.submit t(@file.new_record?? '.create' : '.update'), :disable_builder => true %>
<% end %>