Thanks for that Ant.  I've managed to create the config file & rebooted.  It now reboots to the attached screen.  I'll go through Xen's procedure again & see if i can spot any mistakes in what I've done.

In the config file, should the address of the file be written as:

exec --no-startup-id xfce4-terminal -e "node /home/pi/index.js" --hide-menubar --hold

or:

exec --no-startup-id xfce4-terminal -e "node index.js" --hide-menubar --hold ?

I've stuck with the second of those lines.

I've ploughed through Xen's (very clear) instructions a couple of times and can't see any errors in what I've done.

I'm assuming that raspi-config should continue to be set to log me into the console, not the GUI?

That screenshot shows i3 running. So it's mostly there. The bottom bar is showing though - need to get rid of that. And the terminal doesn't seem to be running - need to fix that.

Either of those lines should work since index.js is right in your home folder (the canonical one's a bit 'better', it'll still work if i3 or node decide their current working directory is not home).

That screen is so cute  :-$

I'm going to test some things and then post again.