How to make all UAM-protected posts private?

Marked all the UAM-posts private with the following SQL query:

UPDATE wp_posts SET post_status = ‘private’ WHERE wp_posts.post_status = ‘publish’ AND wp_posts.ID IN (
SELECT CAST( object_id AS UNSIGNED ) AS post_id
FROM wp_uam_accessgroup_to_object
WHERE object_type = ‘post’
)

then uninstalled the plugin and removed tables used by previous version of UAM:

DROP TABLE wp_uam_accessgroup_to_user
DROP TABLE wp_uam_accessgroup_to_category
DROP TABLE wp_uam_accessgroup_to_role
DROP TABLE wp_uam_accessgroup_to_post

with enabled UAM, Nginx slowlog shown me the following stack trace:

script_filename = /home/slogpost/www/index.php
[0x0000000002a98d38] mysql_query() /home/slogpost/www/wp-includes/wp-db.php:1199
[0x0000000002a989a8] query() /home/slogpost/www/wp-includes/wp-db.php:1437
[0x0000000002a98618] get_var() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamUserGroup.class.php:926
[0x0000000002a97b48] _isPostInCategory() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamUserGroup.class.php:951
[0x0000000002a971c8] _getFullPost() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamUserGroup.class.php:691
[0x0000000002a96f40] _getSingleObject() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamUserGroup.class.php:592
[0x0000000002a96498] objectIsMember() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamAccessHandler.class.php:323
[0x0000000002a954d0] getUserGroupsForObject() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UamAccessHandler.class.php:386
[0x0000000002a947a0] checkObjectAccess() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UserAccessManager.class.php:1674
[0x0000000002a941a0] _getTerm() /home/slogpost/www/wp-content/plugins/user-access-manager/class/UserAccessManager.class.php:1733
[0x00007fff07973000] showTerms() unknown:0
[0x0000000002a93870] call_user_func_array() /home/slogpost/www/wp-includes/plugin.php:173
[0x0000000002a8fa88] apply_filters() /home/slogpost/www/wp-includes/taxonomy.php:1465
[0x0000000002a8f5f0] get_terms() /home/slogpost/www/wp-includes/category.php:51
[0x0000000002a8e660] get_categories() /home/slogpost/www/wp-includes/category-template.php:445
[0x0000000002a8dfb8] wp_list_categories() /home/slogpost/www/wp-includes/default-widgets.php:485
[0x0000000002a8db30] widget() /home/slogpost/www/wp-includes/widgets.php:182
[0x00007fff07973300] display_callback() unknown:0
[0x0000000002a8cd40] call_user_func_array() /home/slogpost/www/wp-includes/widgets.php:904
[0x0000000002a8c818] dynamic_sidebar() /home/slogpost/www/wp-content/themes/classic/sidebar.php:12