Vertigo is the fear of heights. The high moving platform should be no problem in this level.
When you first start out turn to the right and pick-up the first gem, then turn around and turn to the left to get the Shatter Ammo. the two Wakka's that are on the lowest level take quite a few shot to destroy, so strafe around them until you have a few open shots. There are a total of four gems, the Minigun, the Shatter Ammo, and the Guided Missiles on the lowest level.
Either ramp you take to get to the second level is fine, but it's best to equip your Minigun so you can take out the two Gun Turrets easily. Once you get the four gems on the second level take the narrow walkway to the first elevator. If you're running low on front shields, get on the elevator sideways so that when you get to the top you will take the shot from the Gun Turret in the side and not the front. There is no way to avoid the shot.
On the third level destroy the Gun Turret immediately, get the gem near the first elevator, and then destroy the Bomber. Next get the gems on either side of the second elevator and head up to the top level. Just like the first elevator, you will get hit at the top, this time by a Missile Turret. Take the hit in the side if you need to reserve your front shield.
On the top level make your way to the slow moving platform after destroying the Missile Turret.
Get the easy gem and the final gem on the other side of the exit block. If you have to wait for the
slow moving platform, aim at where the Missile Turret was because it might respawn while your
back is turned. Finally touch the exit block to end the game.
Don't forget that if you play around with the Guided Missiles to fly around the level, they only work for about fifteen seconds, then you are reverted back to your rig. Don't accidentally fall off the platform.