Different default controller and other things

[eluser]Unknown[/eluser]
Hey folks,

my first problem:
I'm developing an application with kind of a entry point. The default controller is either the registration or your profile. How to achieve this effect? I don't want to use redirection (would look pretty messy to have "url.com/registration" and "url.com/profile").

2nd problem:
My application will consist of different elements (e.g. header, which consists of different elements (notifications, ...), content, footer, etc). I've got two different solutions: 1) HMVC, 2) Libraries. I think (1) is the better way, isn't it?

Thanks