The XE DB management GUI tools are not standard components of APEX, but special applications developed in APEX that are included in the default XE installation. As they are not part of the standard standalone APEX installation they are lost when you upgrade using this.
By upgrading to APEX 4.2 you have removed the database management GUI from XE. The only GUI admin tools provided by APEX are for managing the APEX instance and workspaces.
Backup and recovery and other basic DBA tasks must be performed using external tools like SQL*Plus and SQL Developer.
Use the Oracle Database Express Edition (XE) forum for XE database questions and this one for questions relating to application development in APEX.