A few problems I have noticed.

[Max1996]

First of all, after the nrw update on my Z, when I start the camera, there is a portion completely black, covering around 20% area which has the buttons of capturing and video. I can see the buttons but the rest area is black. But. Front camera is ok. Also I think my top left back panel is starting to raise. I hope thats covered in warannty.Thirdly, my photos take way too much time than before to load.I have bought sony mobiles everytime and I keep my faith in them. Hope I get the fix fast

[Uliwooly]

if you have the resolution set at 12mp/13mp that's normal, change it to 9mp. 

As for the back panel, take it to a Sony repair center. 

Where are you saving your pictures? (SD card or Internal Storage) which camera settings? HDR on or off? Night mode settings? Superior Auto? etc

[JakeSully]

he is talking about black box where buttons is is covering 20% of screen when using camera.

oh wait mybad he did state about back panel xD

[Max1996]

9 mp fixes the prob But isn't 12 mp more better?why is there a black box.coming anyway?, and If I take it to sony repair center, will they do it for free, I mean, warranty? , also, my camera settings ar superior auto. 9 mp nothing else and save in sd card

[Uliwooly]

There's no way around it, if the picture its at 12/13mp the ratio will be 4:3, and your screen its 16:9 more or less.

As for the back cover you have to contact them.

Is your SD card a class 2 or class 4?  

[Max1996]

How do u see that?? And I shifted to internal storage a week ago btw. 

[Uliwooly]

unmount the SD card > it should have a circle with a number inside (the circle) 

[Max1996]

ok got it. class 4.