At the end of the day, all people who have placed in the top 150 are placed into a lottery for the collectors.
There are 2 separate lotteries, one for standard and one for extended...
Since there are 12 DT's in a day, there are a total of 12x150 spots for the lottery, or 1800 spots in both the standard and extended lotteries.
Q:I placed in the top 150 several times in a day! Does this mean I get multiple rolls for the Cr's?
A:To my knowledge, no; however, each additional top 150 place you make DOES take away the spot from someone else, so you are increasing your odds (though very marginally).
Q:I placed in the top 150 in standard, then in the top 150 in extended! Does this mean I get to participate in both the standard and extended lottery?
A:Yes, you do. You have a maximum of one chance in both lotteries, though.