i found some mistakes steps from boston mania
How to -> For who still have the old 2.1 or 2.2 rom and want to put this amazing rom, need to do this steps:
1- download 2.3 nb0 rom cm7.0.2_z71_battery_memory_fix.nb0
2- update your phone to 2.3 rom using SUT SUTLR_v1.7.0
3- download cm_z71_full-88.zip and update kernel SuperAOSP 8.0 RC2 to your memory card
4- on the recovery menu apply the new rom build update and after that apply the battery and memory fix
5- reboot your phone and that's all

You have the 2.3.4 rom !!!
Thank you to EVERYONE involved in Cyanogen! Enjoy!
instead of SUT 2.3 1st, actually from 2.1, we can direct root from rom manager the cm_z71_full-88.zip in recovery mode,
is it right?
yeah, if you're on 2.1, you can actually use rom manager to install cm 7 directly
..remember to install gapps as well.