For that i dont have the answer.
If i usualy need specific instances i just create more then one of the same object, and then pick the instance out of those that i need.
For example:
I have an object with variable slot1.
Event
right click
-if (obj.slot1 == 'bullet1') then
-- spwan bullet1 object on layer ....
-if (obj.slot1 == 'bullet2') then
-- spwan bullet2 object on layer ....
My problem is I have more than 50 bullet.
<img src="smileys/smiley19.gif" border="0" align="middle" />