Generally if you apply a RowStyleSelector while having an alternation defined, then it will be applied only for the non-alternated Rows. If you would like to apply a StyleSelector for the alternated rows also, then you should additionally set the AlternateRowStyleSelector.
My suggestion is to not use alternation at all as it slows down the performance of RadGridView.
As to your second problem, the style will be applied as soon as the user commit the row edit.
Let me know if you have any additional questions.
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