There was an Art of Defence map on normal Generals which me loved, And when we upgraded to Zero Hour, we couldn't play it.It was "art of defence se4 v1 - 18".

My questions are:

If there a verson of this AoD for Zero Hour?
If not: Is there a way to covert it form Generals to Generals: Zero Hour? How?

Thank you for your time.

I would contact  the author.

Standard skirmish Generals maps can be modified for ZH by replacing waypoints, i.e. Start Positions with ZH world builder and also removing and then adding players using the Add Skirmish Players button. As this map has scripts, you can try just adding the players without removing vanilla players to retain scripting. Not 100% sure that will work though.

I have seen that name on the 2vs2 lobby, if i encounter it i will play it and then post back here.
So yes, probably somewhere someone has converted or copied it, i`ll aee if i can get it for you.
-bat66wta66