i figured it out.
its drag-and-drop, but not so straight-forward. got this info from one of the random walk-through floating around (little sad i had to go that deep to find my answer. hate reading those on games i havnt finished once through)
-open inventory
-select (single left click) the first item.
-drag and drop second item onto the large PICTURE of the item. not the icon, but the large picture on the left side of the inventory
ya know, it always some little shit like this that i get stuck on, yet i can figure out some really elaborate puzzles on my own.
edit: i cannot mark my OWN post as a solution!? someone quote me and ill credit you :)
2nd edit: its called a GRAPNEL in the game. i have never noticed the difference in the terms... ive always said, "grappling hook." maybe that is why all my searches went no where. i learned something in all this and have grow... as a person. hahahahal, thanks for listening!
Post edited May 25, 2012 by SapienChavez