Here are some answers for you
I have a little girl of 3 yo. Do I need to buy a Rail pass for her?
Infants under 6 years old travel for free on the JR system provided she can sit on your lap if the train gets very busy and is travelling with at least 1 Japan Rail Pass holder. We have more about child validity in our blog
I have a very large name: First Name: Miguel Angel Second name: Ortega Martinez. This is how is printed in my passport. Do I have to cap my complete name in your site at the time to order the rail pass?
That's fine. When you order your rail pass, please enter your full first and second names into our system. We will make sure your name is capitalised on your ticket, so you can enter your information naturally.
Do you ship Rail pass to Mexico City? If affirmative, please provide cost.
Yes we do ship to Mexico city. Current delivery to Mexico is $30 USD and takes approx. 3 days once dispatched.
Hope this helps!