i am trying to install kali on my macbookpro 8.1 through usb as my superdrive is broken, i tried many usb and usb iso tools but in refind when i select to boot from the usb it shows no bootable drive found but on startup if i press option key and boot to the efi mode it says no suitabe video mode found booting in blind mode and it goes to the kali startup screen and if i select other username:root pass:toor it says authentication failure. please help sir