El changelog oficial es este, rom oficial hay, pero no se porque los de xiaomi.eu no la sacaran
MIUI 7 China Developer ROM 6.3.3 Full Changelog
Lockscreen, Status Bar, Notification Bar
Optimization - Animation for switching between Notification shade and Global search (03-01)
Fix - Lock screen settings from third party themes couldn't be applied in some cases (03-02)
Backup
Fix - Interruptions or unsuccessful file transfers in Mi Mover in some cases (03-01)
Global Search
Fix - FC in some cases