So I know you have to unlock boot loader in order to flash a custom rom, however if you power off your phone and hold (I think) power, home button and volume up, it gives you a blue flash custom os screen. Can I flash a custom rom such as parinoid android? And if so will it then work with root access? Because i know on the snapdragon version of the s7 it has a locked boot loader and unlocking it requires a semi non-functional Kernal that makes the phone really laggy and overheat.