In new product I do not see both languages.

Hi,

1. Yes, the translation interface will only appear once you save once the product. That's normal.

2. Regarding the language flags, that must come from the way you setup your menu items.
I would recommend that you don't use Joomla's language system for the translation of your menu items.
Otherwise, Joomla will automatically redirect the user to the connected menu item when you change the current language.
Instead, have only one menu item structure, and translate it with Falang. It will prevent the switch to a different menu item when you change the language and that way you'll always stay on the same page.

3. Yes, that's possible. Here is a thread which provides an explanation on how to do it:
www.hikashop.com/forum/4-how-to/47696-mu...l-productimport.html
The CSV file format cannot be compressed by itslef, so I don't see what you're talking about when you're asking about the compression of the file.