Hi i want to make that Edmund Duke shoting with nuke with long cooldown, but there is always an information OUT OF RANGE, any advice?

The "Nuclear Missile" weapon has a weapon range of 3, so you need to increase the weapon range. Modifying this weapon will also affect the actual nuclear missiles, so you might want to copy the weapon stats to the Edmund Duke siege weapon instead of changing the weapon ID.

And making a unit use the actual nuclear missile is a separate affair (though it's doable).

Starcraft Oppenheimer lol.