Well, it's a little tricky. I think you'd have to at least define several areas where the item can we put to, such as, floor, table, etc. because (naturally) the engine doesn't know which area of the screen is a high place and which is not.
So, define those areas as region entites (making them interactive), name them omething like "floor", "table"... and handle using the item on them in their script (see below).
Next, you need a scene entity representing the dropped item (similarly to the book item in WME demo). Let's assume the name of this entity is "coin_entity" and the name of the coin inventory item is "coin_item".
Then the script attached to those scene areas (i.e. the region entities) would look something like:
#include "scripts\base.inc"
on "coin_item"
{
// play the right animation depending on what area did we click
switch(this.Name)
{
case "floor": actor.PlayAnim("drop_crouch.anim"); break;
case "table": actor.PlayAnim("drop_stand.anim"); break;
// some more cases here
}
// remove the item from inventory
Game.DropItem("coin_item");
// and place the entity where the player clicked within the scene
var Ent = Scene.GetNode("coin_entity");
Ent.X = Scene.MouseX;
Ent.Y = Scene.MouseY;
}
This is a very rough description but hopefully it will give you some ideas how to implement it.