Jock thank you for your work! Everything worked on my H96Max RK3318. The sequence was as follows:
1. switch to beta repository in armbian-config or by changing apt.armbian.com to beta.armbian.com in /etc/apt/sources.list.d/armbian.list
2. run apt update and upgrade at least the kernel, dtb and armbian-bsp-cli-rk3318 packages, then reboot, run armbian-config (Software->Hardware->and on led-conf5)
3. apt install git make linux-headers-edge-rockchip64 -y
4. git clone https://github.com/jefflessard/tm16xx-display.git; cd tm16xx-display; ln -s /boot/System.map-`uname -r` /lib/modules/`uname -r`/build/System.map
5. make install
The clock is ticking, the indicators are working. After the Homeassistant docker.