Is there any particular reason CellEditor in following code will not work. I need to set columns of DataGridControl manually. When I do this columns are displayed properly but editing does not work at all. I have tested different cell editors (standard and read from resource), set AutoCreateColumns to true/false, surrounded column creation code ...

Not all cell editors are created when AutoCreateColumns is set to false. That said, you will need to add a NumericTextBox editor as the RankSeq column's CellEditor.

When working with AutoCreateColumns = false, for the InsertionRow to function property, you will need to manually set CellEditors on the Columns.e.g.:<Column CellEditor=''{x:Static xcdg:CellEditor.TextBoxEditor}'' />  As for your second question, you can find the answer in this thread.