Obviously I tried first the quick guide included in the thread you suggested me.
However that doesn't fix the problem, because what is suggested there is NOT ok to import 'description' and 'keywords' of the images. Based on what is suggested in your thread, I should add manually in ControlPanel 'description' and 'keywords' of the images. That is the real problem and the real pain!!
I have already 'description' and 'keywords' included in a mysql file I am using to import images attributes in the database.
I wrote above a line of this file, I am repeating it below:
INSERT INTO `4images_images` VALUES ('image_id', 'cat_id user_id', 'image_name', 'image_description', 'image_keywords', etc...);
Please focus on that is written in bold, because that is the advantage of this method. It enables you to avoid the very consuming time method to add description and keywords in the ControlPanel. And that is also the regular way to import data for any script I know. However that fails in '4images' because the images added with this method are not displayed when I perform a search for it.