That in EP4
PHP Code:
$category_delimiter = "\x5e"; //Need to move this to the admin panel 
on import (before the your last commit ):

PHP Code:
$categories_delimiter = $category_delimiter;
$categories_names_array[$lang['id']] = mb_split($categories_delimiter, $items[$filelayout['v_categories_name_' . $lang['id']]]); 
Why not :
PHP Code:
$categories_names_array[$lang['id']] = mb_split($category_delimiter , $items[$filelayout['v_categories_name_' . $lang['id']]]); 
[/PHP]

But has you explain, this was a ongoing process, and I quite understood.