Shyam,
a) Could you conform that, latest src js and css have fix for your tooltip issue?
b) We took the reference sample where we had illustrated baselines for you and rounded the dates to make the baseline start, render rounded at the start of the day and end at the end of the day.
We have sent the updated sample htm. Best way to see the changes are through a WinDiff with the previous version you have.
Regards,
-Raja.