Questions about MAIN and FS for C902

Hi, I'm a first timer in flashing an SE phone. I got a european version C902 and I'm intending to flash it to be able to view and write Chinese characters (either Simplified or Traditional is fine). I need advice in selecting the right MAIN and FS, from the following available MAIN's for R3CA038:

A. C902_R3CA038_MAIN_CHINA_MM_RED52
B. C902_R3CA038_MAIN_GENERIC_AO_RED52
C. C902_R3CA038_MAIN_HUTCHISON_HK_AO_RED52
D. C902_R3CA038_MAIN_VODAFONE_AO_RED52

1. Will B work with any FS?
2. Why does A have a different code name (MM)?
3. Does C contain branding for Hutchison HK？
4. Does C902_R3CA038_FS_CHINA_RED52 work perfectly with A?
5. Does C902_R3CA038_FS_APAC-ANZ_RED52 include Chinese? And does it work with A and B? As far as I know my friend's C702 with APAC-ANZ FS does include Chinese input.
6. What's the suggested pair(s)?

Thank you for your time.

First of all - Wellcome.
Second - you can't flash C902 for free , but you can change firmware with SEUS (Sony Ericsson Update Service) and little help of this [Debrand] A2 (Db3150) Tutorial - Top Sony Forums or you can upload ZH.lng and ZH.T9 with w910i change language - Top Sony Forums and a2uploader you will find here a2uploader - Top Sony Forums

thank you for your reply, I'll check those articles out first.