*ignoring previous replies as they are not even good*
Ok ill start with the main problem: you can't make your clone to be with 0 collision and thus you can't create it at your hero's position but near it.
I think the only solution for this would be storing the point and angle your hero is in, then moving the hero to some other place in the map.
Then you will clone him and move the clone to the stored point and face him to the angle.
For the windwalk, add your hero windwalk and order him to cast, and then move him too to the stored point (he will be moved NEAR the point because the clone is there).
If you want this to be MPI, just use arrays.
If you want this to be MUI, use jass.
Oh and just as a side note.
If you don't want to add ability and then remove because the player may see it, you can just base the ability on windwalk.