OK I got a few issues.
Firstly the latest nighlty download for vu zero 4k doesn't boot up. It crashes on load. (unfortunatenly I have no log as I deleted it)
Had to revert to several days back to get it to work.
Secondly, debug logs do not work at all. Turn then off and on and nothing is being shown in /home/root/logs
How can I fix this please - I need to have debug logs on