I'm confused about the objects left in the hotel room (spoilers) +++

How did they get the tooth (unless it was just a random tooth), the figure skating statue?? Did they just get a generic copy of the statue (I noticed the engraving plate on the one planted in the hotel is blank)
My understanding is that the objects were Cass' idea because she wanted to see her mom remembering her. Am I wrong here? Also Vince (Bruce greenwood) is definitely shady. Why does he yawn like that in front of Rosario Dawson at the benefit? Why does he ask her such weird questions? The implication seems to be that he is in a position of authority and betrays that trust just like people in authority positions betrayed Rosario when she was young.
Is there significance to the brick building where Ryan Reynolds drops off the hitchhiking girl in the beginning?
I have also heard that the plot line has a "sick twist" but not sure what it was.
Is there something weird with the way the skating partner wears one black skate and one white one (a trick/gimmick as Cassandra puts it). Is the skating partner playing a part in the "betrayal"
I'm confused. I know atom egoyan movies are about characters/mood/tragedy more than seamless plot lines. I just wish there was a deconstruction of the plot on here somewhere. I really liked this movie