You must be more verbose. Does ubu_create.sh finished without errors? Try ubu_close.sh and then ubu_chroot.sh once again. You can also uncomment set -x from ubu_* scripts and in image /usr/share/ubu_chroot/ For gui try ubu_install.sh (qxcompositor, lxde) and read instruction about qxcompositor on openrepos. BTW slimport support is not in master branch and is untouched since eons.
rm /run/user/100000/wayland-0.lock chmod 1777 /dev/shm export XDG_RUNTIME_DIR=/run/user/100000 export $(dbus-lsunch) QT_WAYLAND_FORCE_DPI="160" kwin_wayland --xwayland --height "$Height" --width "$Width" & ##listen for $DISPLAY and pass it sleep 10 export DISPLAY=:0 xhost + sudo -u nemo bash /usr/share/easychroot/scripts/start_de.sh "$Start_DE"
Start_DE="$1" export XDG_RUNTIME_DIR=/run/user/100000 export $(dbus-launch) export DISPLAY=:0 $Start_DE & sleep 10