Also this is supposed to go into Suggestions & Requests Board.
i dont want any of that "its impossible" stuff, you can jsut just shove it up your little ass
3. Engine change.
.. please tell me you mean changing something in the engine, not replacing it.
Why are you asking us? We don't have a way of modifying the engine source that Badspot approves of.Go ask Badspot to add uniforms for screen textures (with history). We're waiting.
Here you go: https://www.google.com/#q=motion+blur+shader+glslGood luck. I'd suggest starting with getting the blur effect to work just in some fixed direction, then worry about calculating the blur vector.
Why would you willingly add motion blur to any game.