Why do I see different displays when I use the Sprint Burndown Gadget versus the Burndown Chart?

[Mike.Hammer]

I used custom start time for sprint.  In the Burndown Chart I see 71 poiints worth of stories at sprint start and then additional points coming off the total with time.

On the otherhand, the Sprint Burndown Gadget starts at 50 story points, goes up to 71 points and then additonal points coming off with time, but then I see additional points added.  

I don't understand why the two reports would be inconsistent.