Steps to restore Steps to restore Android 2.3.4 Stock ROM from from CyagnoMod 7.1 ROM
Read these steps and give it a try (I succeeded and hence sharing here):
NOTE: You own the risk of following the steps. It is assumed you have knowledge of putting phone in Download and Recover Mode. It is also assumed you are aware of ODIN ROM upgrade process.
1. Put the phone in recovery mode and clean cache partition then reset factory settings/wipe user data.
2. Reboot the phone now.
3. Goto download mode
4. When the phone is in download mode, flash Android 2.3.4 Stock ROM using ODI
N and required Stock ROM files (either one package or separate CSC, Modem, etc.. files)
5. When flashing Android 2.3.4 ROM is done, reboot phone in recovery mode.
6. Now in recovery mode, reset factory settings/WIPE user data and clear cache partition.
7. Reboot the phone now.
Disclaimer: These steps worked for me. You are responsible for following these steps and taking risk. You own the risk of damaging hardware and/or software (bricking your phone) for you phone.