People who lose their IMEI are trying to flash the rom using the old update instructions. There is a new version in the Manual, which I've personally wrote for my versions of MIUI.
It's VITAL YOU FOLLOWING THEM..!
People with IMEI issues simple flash back to an OFFICIAL ROM using ODIN and then follow the instructions within the manual to avoid issues!
Framework Modified Updater FC Issue Resolved New Lockscreen (Activated via Theme Manager) Light Sensor Adjustments SU Issues Resolved 3D Fix Applied Removed Unrequired Files and Frameworks Updated to MIUI 1.6.24 (Change Log at http://www.miuiandroid.com)