these keymaps using first level to redirect to different keycode in inet "evdev" section that won't used in ordinary keyboard.
any keys work as Qwerty when press with Control, Alt or Super.
2-5 levels works as same as 1-4 levels of original layout.
created and tested on Ubuntu 14.04.
make sure backup your data.
download zip, and simply replace files:
/usr/share/X11/xkb/rules/base.lst
/usr/share/X11/xkb/rules/base.xml
/usr/share/X11/xkb/rules/evdev.lst
/usr/share/X11/xkb/rules/evdev.xml
/usr/share/X11/xkb/symbols/inet
/usr/share/X11/xkb/symbols/us
/usr/share/X11/xkb/types/complete
and add:
/usr/share/X11/xkb/types/dvorak-qwerty
you may need reassign shortcuts in system setting.