Hi , funny think i experimented a bit , with the brick-9820.sh i manged to see the Hacked fastboot message already, but however when the tablet started it asked me for the pin (wich i dissabled earlier today before i started, and also did factory reset and wipe cache partitioin). After entering the pin it told me the pin is correct however my data is corrupted and the device needs to be reset , i only coudl choose reset, after the reset the hacked fastboot was gone again. So i retried but this time i wasnt luck with the brick-9820 anymore. SO i retried several tiems and then was lucky with the regular brick.sh.
I also noticed , that after the bootrom-step.sh it says it should reboot to Hacked Fastboot wich however it didnt do, i gues maybe the screen was still not wokring, so instead manually goign to fastboot i directly fired "fastboot-step.sh" after bootrom-step was finished.
After that the FireHD booted to TWRP. In the frist post it recommends flashign magisk through TWRP , is this needed ? I want to change to LIneage OS.