Ctrl-Alt-R opens a root terminal.
Scripts are located at /usr/share/dxt2/3
(check they apply to your situation and edit as needed before running)
Activate TRIM on sda
Run install-trim-sda from root terminal. Important: only for SSD installation. (Changes the scheduler to deadline).
Burn iso to flash
dd if=dxt3.iso of=/dev/sdx status=progress && sync
(where /dev/sdx is your target drive)

Use sync after every usb operation if you work with flash drives a lot).
Refracta tools
Use Refracta Snapshot to create a snapshot of your system and restore it with Refracta Installer. If not already installed run install-refracta from root terminal.
Setup progress
To see what the install script is doing when "Running preseed..." press Ctrl-Alt-F4. If running in a VM just (right) Ctrl-F4.
Customising conky
nano ~/.conkyrc
(not from root terminal)
Customising hotcorners
nano ~/.local/share/hotcorners/hotcorner.conf
(not from root terminal)
Setup Flatpak (DXT3)
Run setup-flatpak from root terminal (once-off)
- this step is already complete in DXT2 - DXT3 is an offline installer and adding a  repo during offline installation is not possible, that I'm aware of).

Installing: Now you can just right-click on any flatpakref file and select "Install Flatpak". Note: the first time you install a Flatpak it will download all the base files needed for Flatpak to work properly, so the first one is a big one.
Background radio without wm (DXT3)
Open Menu > Multimedia > Radio Player and add/edit your favourite station. Enable "Autoplay on Startup" in settings. Leave the player on your station of choice. Then go to Menu > Session and Startup > Application Autostart and enable Background Radio. Reboot.
Disable automatic login
Run sed -i "s/autologin-user=/#autologin-user=/g" /etc/lightdm/lightdm.conf from root terminal.
Install Firefox latest
Run flatpak install flathub org.mozilla.firefox (after having setup flatpak) - at some point this will be integrated.
Replace grub boot image
Run cp yourimage.png /boot/grub/themes/dxt3/background.png from root terminal, in the same folder as yourimage.png.
Upgrade to XFCE 4.14
Run add-mx-repos from root terminal.
Receive notifications of updates to DXT2? No Yes