Downloaded the latest stable CakePHP v2.05 to a Ubuntu Linux platform and extracted it and there is no controllers directory under the app directory to place the hello_controller.php file in. There is a directory called Controller under app with a capital 'C' but no ending 's' .

Either this file goes in the Controller directory or the controllers directory needs to be created. Guess I'll find out...

Yep.

As I surmised, several directories (Controller) in the newest version of CakePHP leave off the plural 's' and are now capitalised which the latter on Linux systems can cause folks some confusion. Windows of course doesn't care as it is not case sensitive.

So, beware code examples referencing sub-directories of the apps directory as some have changed in v2.x.