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.
As I'm new to the framework (2 weeks) - I tried to build a functionallity I already use a lot in my old framework (PRADO). This means combining a GridView with a form. And this in one page, what allows you to select a record from the grid and view the values in the same page without jumping to a new page.