Now wait until the spiked platform lowers and walk over it to get to the platform on  the other side of the room.  The treasure box has rupees, but more importantly the yellow switch makes a new treasure box appear on the other side of the room.  Hover there using the spike platform as before and get the small key.  Leave this room back to the big room.

Now look at the left hand corner of the platform you are on (the one furthest corner from you) and you'll see a small rock ramp.  Use it to get to a platform with a falling blade.  Use your lens to see the ledges behind the blade, then dodge and hover to the platforms and finally to the locked door on the wall.  In this room use your lens to see the invisible spikes on the floor.  Kill the two zombies and a rupee chest will appear.  Now to get all the silver coins here, hookshot to the hookshot targets on the wall.  To get the last one, use your lens to see an invisible hookshot target above an invisible platform.  Hookshot up and hover walk off the platform to get it.  Once you have them all a door will open, go through it.  In this room kill all the bats to reopen the blocked door that shut behind you.  Climb up the steps and pick a bomb plant then toss it into the hole in the top of the giant skull to blow it up and get the small key it drops.  Go back into the last room.  Use your lens and look on the ceiling above the raised platform for an invisible hookshot target.  Use it to get on the platform and go through the locked door.

Now I know this sounds weird but, put on your Iron Boots.  This will keep the fans in the tunnel ahead from blowing you away.  Make your way through the tunnel until you come to a pit.  Watch the fan on the other side of the pit and as soon as it stops blowing, equip the hover boots, walk across, and then reequip the iron boots.  Drop down off the ledge and walk across the bridge to the door.  You can kill the eye above the door that's shooting fire at you by hitting it with an arrow while the eye is open.  In this small room kill the two zombies to reopen the door, play the Song of the Sun (not storms) in the middle of the room for a Big Fairy, open the invisible chest for some arrows, use z-targeting and Navi on the face for a hint, then leave. Use your lens to see a hole in the right wall, then stand even with it.  Look at the fan behind you and when it stops, turn around and equip the hover boots.  Stand on the side of the bridge closest to the fan.  Watch closely and when you start moving from the fan run across to the opening in the wall.  The fan helps blow you across.  Go through the door.

As soon as you walk in this room, look to your right and there's a pile of dirt there.  Blow it up with a bomb, then use your Lens to see the invisible chest containing a key.  Kill the two mummies for another rupee chest and go through the locked door.  Once you're through this door turn left and go to the movable block.  Pull it onto the path of green bricks and then pull/push it onto the face tile under the ladder on the opposite side.  Climb up onto it and go up the ladder.  Hop over onto the ship, stand on the Triforce symbol, and play Zelda's Lullaby.  As the ship moves you'll have to fight two Stalfos.