Firstly it is backup and not bake up.
And why do you need to make the backup as a flashable zip. You're making things more complicated.
Just backup through CWM by going to backup and restore>backup to storage/sdcard1 or 0.
You can simply restore it by going to backup and restore>restore and select your restoration file.
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And on rr 5.0.3 using evolution kernel 1.5