Thanks for confirming and sharing the log. I've sent the wifi firmware patch upstream: https://patchwork.kernel.org/project/linux-…[email protected]/
For other Q's:
1. If using Composite output the DRM connector cannot auto-detect the presence of a display (or the display type) and you probably need to force ouput, e.g. for NTSC add video=Composite-1:720x480@60ie and for PAL add video=Composite-1:720x576@50ie to boot params in uEnv.ini on the SD card. Note that the default Estuary skin in Kodi is designed for a minimum 720p screen so when used with something smaller navigation can be challenging.
2. LE does not support boot/run from eMMC with Android boxes: https://wiki.libreelec.tv/hardware/amlogic#installtointernal
3. No, because the box implements rmii (internal-phy) not rgmii (external-phy) so in the upstream kernel p201 is the sole correct dtb to use. I've no idea why the upstream and downstream numbering for GXBB development boards is different, but it is.
NB: ethmactool "errors" are harmless and can be ignored, it's simply a boot-time script that ensures the Ethernet MAC is unique