I am using OMNI ROM 4.4.4 KITKAT on my Galaxy S2 GT-I9100. I want to install ICS ROM CM9. I have TWRP 126.96.36.199. Is it ok to flash CM9 using this TWRP version or should I install CWM. Please guide me how to use TWRP to install this ICS version. I have read ICS versions require different Recovery Modes due to different Bootloader. Is TWRP/CWM back compatible i.e does the latest TWRP/CWM capable enough to install all previous versions of ROMs. Also guide me how to use TWRP as I am comfortable with CWM.