Change from CM11 (4.4KK) to Omega ROM (4.3 JB)

I would like to change the ROM in my Xperia T from CM11 (based on 4.4 KK) to Omega ROM (based on 4.3 JB). How could I install this ROM ? Are the any tutorial to downgrade from 4.4 to 4.3 for Xperia T ?. Also the CWM I have is V6 and I have checked that this ROM requires the CWM V7 or V8 to do installation. Where could I get it ? Thanks in advance.