para los que no pasa del logo del lg , q esta un segundo y despues pantalla en negro seguid estas instrucciones , probado y funcionando :
This fixed the BLACK SCREEN after flashinf rom.
I installed 4.4 20H with KDZ and then root with ioroot and flashed recovery with autorec.
then updated recovery to TWRP 2.8.7.1 Bump.
Then full wiped
then flashed the rom and after that i flashed Cloudyfa's KK Baseband and then i flashed KK 20H bootloader and then the rom booted.