Just my experience, guess I did something slightly wrong:
-put the 3.2.1 ODEX on the ExtSD
-booted in recovery TWRP 2.3.3.0
-flashed 3.2.1 ODEX
-wyped cache as proposed
-Titanium installed 55 applications
Reboot, noticed that GMail icon was changed, probably as it was not found anymore.
Deleted the green Android icon which was set in its place and noticed that Nova was very slow.
Downloaded GMail and placed it at the desktop (Tray in Nova is now different, not so convenient, might be something for me to change)
Opened GMail and saw my mail, but it kept synchronizing.
Decided to reboot
Although Reboot was choose, the screen went black and nothing happened.
Long press Power on was needed to get it back alive.
GMail was again missing ?
But Nova seems to be normal speed again. Choosing to add a new application is still the same "long list of app" instead of app tray. GMail is now normal.
Reboot again, Gmail again missing
What am I missing here ?