By design when the Grid navigatable
property is set to true
the navigation occurs at a cell level
regardless of the cell is editable or not. That is the cause not to skip the non-editable cells in your grid.
Regarding the other issue you have observed - I am not able to reproduce it locally. Could you please send a simple test project which reproduces the depicted issue? Thus I will be able to observe the problem and advice you further.
the Telerik team
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