My b2evolution Version: 4.0.1

In the administration, on the post/comments page of my "home" blog, which aggregates all my other blogs, I see the following errors on the bottom right side:

Categories

ComicList: The New Comic Book Releases List

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/generic/model/_genericcategorycache.class.php on line 266

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/generic/model/_genericcategorycache.class.php on line 228

ComicList Lists

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/widgets/widgets/_coll_category_list.widget.php on line 303

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/widgets/widgets/_coll_category_list.widget.php on line 314

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/widgets/widgets/_coll_category_list.widget.php on line 315

Notice: Trying to get property of non-object in /home/XXX/public_html/inc/widgets/widgets/_coll_category_list.widget.php on line 326

Fatal error: Call to a member function dget() on a non-object in /home/XXX/public_html/inc/widgets/widgets/_coll_category_list.widget.php on line 333

What's up with that?