You try to tune in to your Will... and you find yourself recalling your vision of this very starship crashing into its resting place. Your Will guided you to this place, and it continues to guide you.
The Force roll counts as Easy and you roll four successes.
Not the most experienced swimmer, it takes some struggling to actually guide yourself underwater. But as you sink deeper into the submerged corridors, you follow your instincts and come to a tremendous metal door, as J7 described.
It is closed.
The blast door sealing the armory wasn't designed for easy access. It will take a great amount of effort to unseal it with the Force (or your Will, as the Shaman would tell you).
You can spend a Force point to automatically pass the roll, or you must make Force rolls and accumulate ten successes to wrench the door open, and between each roll, a Strength check as your lungs start screaming for air. Failed Strength checks will detract successes, and too many failed Strength checks will mean you drowned...
If you can justify how the Dark Side would empower you to complete this task, I will give you a free Force point to use on this...
(Reminder: You have one point remaining.)
You reach out and grasp the blast door with your mind. It has not moved in a long time, and between the water pressure and the rust, it will take great effort to move it.
But you have a knack for this sort of thing, altering your environment to suit your needs. On a pool of eleven dice, you show five successes. Spectacular! You also pass your Strength check. It will only get harder to hold your breath...
Your straining shows this time. You gain three successes and the blast door starts to budge reluctantly, but you fail the Strength check by one, reducing your successes to two. Still, almost there...
Perhaps frustrated with the strain you experience, Azarl pulls out another five successes (reduced to four by failing a second Strength check by one) and the blast door suddenly snaps open enough to enter. The sudden change in available space for the water sucks you through the crack and into the door, dumping you into the armory wetly.
Success! Except now the armory is filling with water.