thanks for your feedback

PHP version is either PHP 4.4.9 or PHP 5.2.12.
Browser tested are Firefox 3.6 or IE 8 (same results).
Concerning changing debug setting in the /config.jcollection.php, what do you want me to do ? I've downloaded the file but I don't understand a word in it ! Do you want me to upload it to you ?
BTW, I can now create an item when registred with newest version (...but still empty).
Couldn't it be a misuse of some global parametres or of the 'types' setting where I have a 'Books' type or of the webservice types settings (none)?