I used Quake 2 3.20 patch over Quake 2 demo (the demo is 3.14 version) and it works with DoD. If you try to play Quake 2 demo it will not work now, because you have updated the demo.
If the controls doesent work right, change them in the control menu or restart DoD.
In the default.cfg moddify the lines below, so the secondary attack will work after that :
The Quake 2 demo and DoD is less now in Mb size also.
DoD single player works, i reached the second map. QeffectsGL doesen't work.