Question [Q] White Screen

Hi guys I just installed CyanogenMod on my 10.1 galaxy mini 2 for the moment I happen to be running fine (except for some lagg). I have a problem ... when I end a call (to be precise when I move the cell from ear x close call), the screen remains blank.
In addition nn I understand how you manage your contacts?!? oO because I have to save x force on google and not on the phone? If any of you can help me thank you in advance...

Ah! forgot I installed the google apps but I found it not gmail, google+ it why?

(sorry for my bad english)