I think I may have figured out how to do things from the virtual terminals to affect the X screen.
The vt for X is 6 so we can do:
chvt 6 to switch to the virtual terminal 6
Next we need to have a little delay, so let's add sleep 4 (you can also use 2 if you think that's a bit faster)
We also need to add "export DISPLAY=:0" to set the X display.
Then to change the user, we use "sudo -u knoppix "
So to do xrandr and change the resolution: (this is pretty useful when you mess around with screen resolutions that cause a blank screen)
Hit CTRL+ALT+F4 to switch to VT 4: then type
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix xrandr
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix xrandr --output HDMI-1 --mode 800x600
To launch terminator:
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix terminator &
To open the main menu:
chvt 6; sleep 4; export DISPLAY=:0; sudo -u knoppix lxpanelctl menu
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