I have a TB S, and I installed ALarm. A little problem still remain about the Bluetooth, which is not available.
You may look at my
post and my first
oneSo, summarizing the procedure, it is pretty simple. You should grab a u-boot and put it on the eMMC or SD card, then prepare your partitions to load the system. I'm using Armbian u-boot. You should inform the u-boot where to find the partition to boot from. Make sure you got the latest dtb and you'll be able to get ALarm running.