Disclaimer: Flashing custom firmware is done at your own risk.
Rockchip uses a specific file structure for their updates, typically ending in .img . To repack firmware, you cannot simply use a zip tool. You need the heavy artillery.
If you have a working firmware image for your specific board, repacking it from a backup can serve as a lifesaving rescue tool.
Change display brand signatures to bypass app compatibility blocks. Customizing the Boot Animation
Modified versions of stock firmware often remove bloatware. Compatible versions include those for the paired with specific Wi-Fi chips such as the LibreELEC:
If you can tell me the (e.g., MX4VR_V1.1, MX4VR_V1.3), I can try to help you find the correct firmware link .