You'll need to fill out everything, including the address fields, in order to download her.
I got that issue as well, though I thought it would have only been the mandatory fields that were necessary, but it says on the page that you need to fill out all the registration information. So, you'll have to put a fake address if you don't live in Japan lol.
The trial is 1.6 GB.
EDIT
You must also register (tick box) for the email magazine in order to download her.
She's available for both Windows and Mac users.