I’ll get back to you about the booting from USB thing later.
To answer your questions in the second post:
the device lists the system UEFI version as 106.1624.768 1.5.2 (as a troubleshooting step i did update fog from the git repository) I’ve tried all kernels from 4.12.3 and upwardsthe complete list is:
4.12.3
4.13.4
4.15.2
4.16.6