Inception Question

So, when I was watching the movie, fantastic as it was, I noticed a few holes:

Why, if there's no gravity in the hotel because of the free fall in the van, does the snow fortress not have the same effect?

Does Cob. Actually spin the tip in Youduf's basement? I missed it.

And doe anyone have definitive evidence as to whether it stiopped spinning or not?

>>8
That still doesn't explain 491

528=Perceived re-population needs
???=Digit space paradox 37
491=Reality re-created