z71 phone hangs on logo after restoring default ROM

[Gyrocopter]

I'm noob sorry. And my phone is rebranded the name in my country is Cherry Mobile Nova which is based on z71 etc.

I recently backed up my default ROM with RM and after that I updated it using cyanogen 7.0.2 (Gingerbread). Then I have other issues/problems with CM7. The Wi-fi doesn't work it is stuck on scanning mode then I decided to go back to my default ROM.

And another problem, I got this message "MD5 Mismatch!" so I follow some steps to fix this (in the emulator something on the phone I done something that fixed the .md5)

Then after that I restored my default ROM. I got no problems restoring it it said "Restored complete". I rebooted my phone to see if it work then I'm stuck on the Company logo! I had no back up of CM7 ROM because I thought my old back up is perfect because it is the default ROM. I tried clearing the cache and do a factory reset on the recovery but it doesn't work.

Help please. I really need your help my phone is just new almost 1 week then I bricked it