You can control the arrangement of the RadTileViewItems using the RadTileView.ColumnsCount property. Setting it will force the RadTileView to create rows depending on the number of the RadTileViewItems. Furthermore, you will be able to control where and how the items are ordered using their Position property.
This approach is demonstrated in the attached project. Please take a look at it and let me know if you need any further assistance.
Pavel R. Pavlov
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