I am afraid that the RadProgressArea control cannot be used in a similar to the described scenario, because all of its instances will be updated in one and the same time.
On a side note, thought, we are currently implementing a new RadProgressBar control and achieving the described functionality with it will be really easy so I would suggest that you wait until our Beta release (scheduled for the beginning of October) and try it. The RadProgressBar will be a very lighten version of the RadProgressArea containing only a progress bar and label.
I hope this information will be helpful for you.
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