I have started to set up a new CCGX and wanted to do that over LAN.
It turns out that even though you enable 'Enable on LAN' the access is denied.
The exact error is 'QVNCServer configured to use a password, but the file containing the password can't be read. Disconnecting!!' with the default settings.
The solution is to select 'Disable password check' first, after that access is ok.
I think it should be documented on https://www.victronenergy.com/live/ccgx:start at the explanation for the 'Enable on LAN' option as a prerequisite