Hi George ,
many thanks for your polite help.
You are very clear so I'm proceed as you suggest me:
1 I've enable the override in menu and set the "default main category" as my need. Otherwise my articles would remain orphaned by category

2 I've put in the form.php file
Code:
<?php if ($isnew && $this->menuCats) : /* MENU SPECIFIED categories subset (instead of categories with CREATE perm) */ ?>
<div style='visibility:hidden;'>
<div class="flexi_formblock">
<label id="jform_catid-lbl" for="jform_catid" class="flexi_label">
<?php echo JText::_( !$this->menuCats->cid ? 'FLEXICONTENT_CATEGORY' : 'FLEXI_PRIMARY_CATEGORY' ); /* when submitting to single category, call this field just 'CATEGORY' instead of 'PRIMARY CATEGORY' */ ?>
</label>
<?php echo $this->menuCats->catid; ?>
</div>
3 I've copy form.php in the override dir of the template
So now the formblock is hide !!

but I've some empty rows from title to item type
About the upcoming v2.0.3 there is a different method and I understand that this second method is more flexible for the customization of the layout. Right?
In practice with v2.0.3 I can customized http://mydomain/components/com_flexicon ... ontent.css and copy it in template/mytemplate/css so I can custom at 100% the layout. Right?
Upcoming v2.0.3 are days, weeks or... ?
Have a nice day
P.S. for new version of Flexicontent don't exist the Italian translation. Right?
If don't exist I'll provide translation and send you