Hello, to solve the brightness problem do the following. Start the macbook with catalina or bigsur, open the steellite app and in the second tab change the value of the id panel to A039 then click on write to eeprom, close the steel and restart the macbook, with that the system applies the correct values at startup and the backlight level is corrected. I advise you against playing with the eeprom and its values and always make a copy of the eeprom before touching anything. Luck.​