Wow, this is very cool. The beginning is quite cinematic- a long intro, a detailed tutorial, that's cool, it makes the vibe. Also I can note your cool work with sound (it really reminded me of Hans Zimmer's works with his "deaf technical" sounds). Chic atmosphere and feeling of discomfort - I was scared :)
+ about player movement - it's slow and some may consider it as minus, but for me it was more of plus, since its slowness is really similar to wearing a real space suit (I guess), and that's cool.