I needed British (dd/mm/yyyy) formatted dates throughout my application but found it very difficult to find examples of how to do this - until I found this excellent forum post http://www.yiiframework.com/forum/index.php?/topic/3649-dealing-with-i18n-date-formats/
Using CActiveRecord->updateAll() and CActiveRecord->deleteAll() with scopes and criteria requires some tricks that are explained in this article. While findAll() , find() and some other methods use scopes automatically, updateAll() and deleteAll() do not.
I found a standard Yii app's protected folder structure nearly perfect. With a few simple moves and a little bit change to the code, I managed to bring it to the level, which I found as fully perfect. I want to share my point of view, in case someone would like to use this structure as well.