On a Nexus 5 D820 with the latest Google stock images installed. Note: data formatted as ext4.
Steps taken:
1) flashed hammerheadcaf TWRP
2) wiped all data
3) flashed CM13 CAF zip
4) 2 errors, same: unknown command: [log]
Power off, and then attempted a boot. Nothing. Just a black screen. Do I need an older Nexus 5 Bootloader/Radio Image?
Edit: This may be screen-related. My N5 has had its screen replaced, and others seem to possibly have a similar issue.