1. JS and CSS includes don't exists in drupal header

2. Shortcode don't work in prestashop

3. How to update the gallery to full version from lite

Please go to your configuration -> Text formats -> Filtered HTML ( or whatever text format you are using) - > Configure 

then you will find a check box with "Unite Gallery - Provides unitegallery shortcode filter." and check that, and don't forget to Uncheck "Limit allowed HTML tags" if it is checked. Save configuration.

When you add unite gallery short code to the body of your content don't forget to select a text format that we configured earlier.

Then It works perfect. 

You put shortcode in CMS page and it doesn't work? You still see the shortcode?

If this is the situation, please delete this file: cache/class_index.php

and the shortcode will work.

There is update plugin" button in galleries view.

Please press on it and select the full version zip.

All of the contents will remain. No worries.