Even experienced users make mistakes. Here are the top issues with "xz000g3 firmware full" searches:
If the web GUI hangs after a full flash, clear your browser cache or use incognito mode. Alternatively, access via TELNET (port 23) and run firstboot -y to reset all settings. xz000g3 firmware full
No. The Realtek chipset is not fully documented, so OpenWrt and LibreCMC are not available. The "full" firmware is always proprietary. Even experienced users make mistakes