I tried several dtb files, but I always give the following error message:
One of BOOT, SYTEM, DATA or DTB partitions is missing.
Make sure that you are using a correct device tree and a device with internal memory!
so, you have downloaded the latest coreelec image file, burnt it to sd card or usb, & then from the devices trees folder have tried all of the dtb files?
installtointernal is something we provide on an as-is basis and don’t really provide support for, your welcome to add it to the kernel yourself and we will merge any pull request sent to us so it is included with future builds.