Errors and no download files since update

Have just updated plug in and have these errors showing both on the back and front end:

Notice: Undefined index: page in /var/www/wp-content/plugins/feedblitz-feedsmart/FeedBlitz_FeedSmart.php on line 30

Notice: convert_to_screen(), add_meta_box() was called incorrectly. Likely direct inclusion of wp-admin/includes/template.php in order to use add_meta_box(). This is very wrong. Hook the add_meta_box() call into the add_meta_boxes action instead. Please see Debugging in WordPress for more information. (This message was added in version 3.3.) in /var/www/wp-includes/functions.php on line 3370

Notice: convert_to_screen(), add_meta_box() was called incorrectly. Likely direct inclusion of wp-admin/includes/template.php in order to use add_meta_box(). This is very wrong. Hook the add_meta_box() call into the add_meta_boxes action instead. Please see Debugging in WordPress for more information. (This message was added in version 3.3.) in /var/www/wp-includes/functions.php on line 3370

Notice: convert_to_screen(), add_meta_box() was called incorrectly. Likely direct inclusion of wp-admin/includes/template.php in order to use add_meta_box(). This is very wrong. Hook the add_meta_box() call into the add_meta_boxes action instead. Please see Debugging in WordPress for more information. (This message was added in version 3.3.) in /var/www/wp-includes/functions.php on line 3370

Notice: wpdb::escape is deprecated since version 3.6! Use wpdb::prepare() or esc_sql() instead. in /var/www/wp-includes/functions.php on line 3201

Also, all my download files have disappeared. Please advise

https://wordpress.org/plugins/download-manager/