Sri,
What you have mentioned is a problem I have been facing since a long time...
Initially, I thought it's some Java setting problem with my PC - but it existed in another PC as well. After reading your post, I guess this problem is universal.
That is why, at 9:55:30, I open charts of all scrips (2-3, incl Nifty) which I have selected for trading for the concerned day.
Once you have done this, you can change the TF of the chart AND ALSO open another chart of the SAME scrip anytime during the trading hours.
But, if you try to load a chart of a scrip, which you did not initiate at 9:55, it will not be accurate.
Also, if you restart you PC during trading hours, the same problem will arise. Any chart you try loading after PC restart, will be inaccurate, and will begin from the time you opened the chart plus some data from 10 to around 10:30.
That is why, I have opted for SK's TT as a backup and also to get access to 5day intraday chart