Please have a look to the following url.
The header menu is not working properly. the items are coming in to the second line etc. As I should have "Checkout --> Pay" and "Order Recieved" under "Checkout" as submenu. When I change the theme to Twenty Eleven then it works fine. I copied all the twentyeleven/style.css code and pasted in my-custom-theme/style.css and that still didn't bring the menu change.