We already have plans to add a background that will offer the desired panorama/parallax effect, but I cannot provide a firm ETA for it, because there are still other major features with high priority left for implementation, like databinding. You can follow the release notes
to see when it becomes available. It also offers an RSS feed.
We also have an idea that a property for the scroll speed may be needed and I have created a public item where you can comment on its implementation (e.g. whether it should be an enum like slow|medium|fast or an integer form a set interval, etc.). You can find it here: http://feedback.telerik.com/Project/108/Feedback/Details/53553
On adding tiles - they should be added to the Tile collection of each TileGroup, as it is an IEnumerable collection. You can find an example of this in the following help article: http://www.telerik.com/help/aspnet-ajax/tilelist-server-side-programmatic-creation.html
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