Good Ambient Creation
I assume your intent was more to make an environment or a mood setting, rather than to make a "song" or "music". To that end, you did well.
As far as submachine sounds, Fruity Loops has some decent noises, although right now I can't remember exactly where to find them within fruity loops.
Hey, turn up that master volume!
It might be Ambient, but that doesn't mean you set the volume to one! Turn up the volume and add some more dark pads and sound effects like water droplets. If you do that, it would make it sound a whole lot better with a higher score. Because it was a good idea, but the idea wasn't put through very well.
Keep it up!