I am posting the reply from your support ticket here if anyone encounters the same problems. If you have any further questions, please write to us in the formal support thread.
Please note that there are also top and bottom paddings for the cells in RadTreeList and if you do not clear them, you get 7 more pixels in height. You can clear the default paddings with the following CSS rule:
div.RadTreeList .rtlTable .rtlR td, div.RadTreeList .rtlTable .rtlA td
if you set height for the rows they should appear equally high, no matter if they have an image or not.
As for the second problem, in the default scenario you should not get such appearance on selection, can you confirm that you have not customized the backgrounds in the grid. If you have, make sure that the selected row has a background color #9DD672 for the Hay skin:
the Telerik team
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