Downloaded the hotfix 2012.2.0713 and the app bar issue is resolved. Hope this internal build has not introduced any new bugs in the controls that I am using.
As per the 2nd issue about TimePicker over a Popup, see the screenshots attached herewith.
- First check the screenshot "Popup1 on Page1". I am using a popup that contains a DatePicker and a TimePicker.
- Then check the screenshot "TimePicker1 on Pipup1". This is what I get when tap on the TimePicker. You can only see the title "SELECT TIME" at the top and the two icons in the ApplicationBar at the bootom. But the time selector digits are not seen. They are obscured by my popup's display.
So the TimePicker works fine if I use it directly on a Page. It doesn't work if I use it in a popup.