This rom has solved my Connection problem or invalid MMI Code and Undefined additional service. Contact customer center problem. So I am using it since some days and don't see any bugs. Flashing method:
TWRP recovery for flashing through Odin and Odin are attached. You will find videos how to flash custom recovery using Odin. Videos relating to that you can find on youtube.
Install TWRP. Boot in recovery (press volume down+home button+power button till you see the boot screen coming on and then release them). Backup your current rom. Do factory reset. Do data, dalvik and cache wipe. Install downloaded "miui_E300_gtbluesky_5.11.22_V7_4.4changed.zip". Reboot. First boot may take a bit long time. If it is stuck at the samsung logo then boot in recovery and do a dalvik and cache wipe and reboot. Do not use MIUI updater to update your MIUI version. It will give problems like touch screen not working properly.
The developer of this rom is ''gtbluesky''. His XDA page is - http://forum.xda-developers.com/member.php?u=4474974
His twitter page is - https://twitter.com/gtbluesky
I have asked for his permission to post this rom and am waiting for his reply.