Wipe full except SD card, flash the ROM
Run A2SD script from terminal emulator provided
Go to Settings -> Launcher -> Homescreen -> Check "Stretch screens", Un-check "Scroll wallpaper", Check "Wallpaper quick render"
Make sure to check your APN settings are correct and change if it's different. Turn of GPS if not used, tap 7 times on Build Number to get Performance and Developer options.
Reboot and wait for 5min
To wszystko powyżej zrobiłeś bo mi od 10 dni chodzi jak należy w zasadzie po jednym restarcie, na 5.2 troche wolniej reaguje więc chyba wrócę na 5.1.