Since Rails 2.3, render_component plugin is needed for nested and embbeded scaffolds. It works with rails-2.3 branch from ewildgoose repository:
script/plugin install GIT://GITHUB.COM/EWILDGOOSE/RENDER_COMPONENT.GIT -R RAILS-2.3

If you want localization check out:
  http://github.com/edwinmoss/active_scaffold_localize

This fork's variances from the core repository:
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******* Candidates for Core **********
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- Added Actions:
  - :export - (csv) uses customized selection of columns and the filter setup in search action
  - :print - (html, pdf)
  - :refresh - an ajax refresh of the list
  - :customize - list column customization
- Localization is supported per Rails example - not in the plugin. Only 'en-us.rb' is included in plugin.
- Generator support
  - script/generate active_scaffold user
- :config block additions
    ActiveScaffold.set_defaults do |config| 
      config.security.allowed_actions << :verify # Add your own actions to security
      config.left_handed = true
      config.one_column_list = true # suppress the grid look, in favor of a free format per row
      config.upper_case_form_fields = true
      config.show_actions_column = false # hide the action columns
      config.subform.layout = :horizontal # Specify your preferred subform layout
    end
  - options[:observe_method] and options[:observe_controller]
  - secure_download - support for putting your file repository somewhere other than public and allow authenticated download access only
    - In active_scaffold config block:
      column#options = {:secure_download => true},
    - In your model (if using file_column plugin):
      file_column :package, :root_path => File.join(RAILS_ROOT, 'files')
- :field_search additions:
  - Filter operators for other data types including 'BETWEEN' for:
     #condition_for_string_type
    #condition_for_dhtml_calendar_type
    #condition_for_exact_type
    #condition_for_record_select_type
    #condition_for_multi_select_type
  - js :failure action is populated
  - Loading indicator support
  - default params for like_pattern param on all helper methods
  - rid of active_scaffold_search_multi_select in favor of active_scaffold_search_select
- :list additions:
  - render_action_link has additional param link_html_options = {}. This allows for example the ease of performing window.open in the onclick and redisplay row in one action link - like reading pdf generated email in a new window and marking it as read.
  - Left or Right-handed format (see config block above)
  - do_list_by_sql method - build your list with a sql statement
  - Handle no_entries_message via t() method
  - Stack user created row based actions - limits the width of action column
  - Show that list is filtered by showing a link in column header of action column that allows for a quick reset.
  - #make_available_method override method - specify in the model if value is available, useful when a field is dependent on other fields
- :create/:update additions:
  - Column#allow_add_existing (Disable add existing controls on subform)
  - Exception handling in active_scaffold_input_for. It is nice to know you just messed something up in the config block.
  - :boolean types are treated as checkboxes by default
  - All helper methods include - ,options = {})
  - #form_ui => :hidden
  - Support :horizontal or :vertical sub-forms
  - ActiveRecord Error messages display at the top and the bottom of forms - just in case you have a really long form and the browser does not auto-scroll to show you the top of the form on submit.
  - A few helpers:
    - active_scaffold_add_existing_label and active_scaffold_add_existing_input
    - remote_image_submit_tag
- Specify action links with a symbol or a string
- SemanticAttribute integration - inspect column type and required-ness from SemanticAttribute
- RecordSelect integration - I use it all the time so I make sure it works.
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******* Candidates for Core **********
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- Added Actions:
  - :revision - supports acts_as_revisionable
- Migration #timestamps includes: 
  - deleted_at
    - t.timestamps :deleted_at => true # If you want a deleted_at field
  - lock_version
    - t.timestamps :lock_version => false # If you don't want lock_version field
- :list additions:
  - display and calculation formatters for:
    - :usa_zip
    - :usa_phone
    - :usa_money
    - :percentage
    - :ssn
- :create/:update additions:
  - Force all fields to be UPPER_CASE or
    column#options = {upper_case_form_fields => false}
    - :form_ui supports additional types of:
      - :yes_no_radio
      - :true_false_radio
      - :usa_zip
      - :usa_phone
      - :usa_money
    - client-side js formating for:
      - :usa_zip
      - :usa_phone
      - :usa_money
      - :percentage
      - :ssn

    
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** For all documentation see the project website: http://www.ActiveScaffold.com **
**********************************************************************************

ActiveScaffold plugin by Scott Rutherford (scott@caronsoftware.com), Richard White (rrwhite@gmail.com), Lance Ivy (lance@cainlevy.net), Ed Moss, and Tim Harper

Uses DhtmlHistory by Brad Neuberg (bkn3@columbia.edu)
http://codinginparadise.org

Uses Querystring by Adam Vandenberg
http://adamv.com/dev/javascript/querystring

Uses Paginator by Bruce Williams
http://paginator.rubyforge.org/

Supports RecordSelect by Lance Ivy
http://code.google.com/p/recordselect/

== Version Information

Please note the following list of Active Scaffold branches and Rails versions. Master will not work with Rails < 2.2

Rails master (edge): Active Scaffold master
Rails 2.2.*: Active Scaffold rails-2.2
Rails 2.1.*: Active Scaffold rails-2.1
Rails < 2.1: Active Scaffold 1-1-stable (no guarantees)

Released under the MIT license (included)