Hi there,
I have upgraded [v1.6.1.24] my website using 1-Click Upgrade Module to the latest version [1.7.6.8] of the PS a week or so ago. Today I realized that it's not displaying 'Pages Configuration' and 'Advanced Customizations' Tabs under 'Design -> Theme & Logo' settings page
Initially I was under the illusion that perhaps this feature has been taken off, till I cam across this YT video ..
which is recorded the same PS version 1.7.6.8 and does display the tabs as well.