You only can move entitiy objects (eg: *.mdl, *.wmb). Right click on an entity in WED, choose Properies and Behaviour. There you have to choose the action you want. A simple move action (without collision) could be:
Code:

---

 
action move_cube
{
	var move_speed = 2;
	while(1)
	{
		my.x += key_cuu * move_speed * time - key_cud * move_speed * time;
		my.y += key_cur * move_speed * time - key_cul * move_speed * time;
		wait(1);
	}
}
 

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