We are aware of the problem, when binding PeriodStart and PeriodEnd properties and we will fix it for the upcoming beta release.
Regarding the second problem that you have - I spent some time researching it, and it turns out that the properties of the time bar control have the corrected values and that only the UI of the control is not updated properly. I will log this problem in our data base and we will do our best to fix it for the official Q2 2011 release.
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