Suggestion would be to select the un-install EP4 link in the top right. This will clear the settings in the configuration menu for EP4, then select the install option that will appear and again set the temporary directory to easypopulate4/

It looks like somehow the upgrade operations were not executed to update the configuration menu which would have also placed EASYPOPULATE_4_CONFIG_TEMP_DIR in the database as one of the configuration options described.