the unlock card

I can't find a way to activate the unlock card, so I can't go any farther in the game. I tried the guide but it just says get the card and use on door.

Did you make the magic steam spray? You need to use this spray on the bottle on the table in the room with the leprechaun, and then you can charge the unlock card on the bottle. It should say so in the SG a couple of lines above the line saying to use the card on the door.