Hello Csaba,

Thank you for contacting Infragistics

We received your support request concerning editing in the igHierarchicalGrid, and this case has been assigned to me. Infragistics is dedicated to helping you solve this issue. Our team and I have done an initial review of your case and I will be reviewing your sample to try and isolate the issue.  I will get back to you tomorrow with more questions or information for you.

The reason you were unable to use the Updating feature was because you did not set a primaryKey value, which is necessary in order to use Updating.  Please see the attached JSFiddle with editing functionality in the top root grid: http://jsfiddle.net/4CrP9/11/ .  In order to do editing in the child grids, you must manually define the columnLayouts of the children and add the Updating feature in these children grids.  Please refer to this sample which gives a great example of editing in parent and child grids: http://igniteui.com/hierarchical-grid/row-edit-template . Please do not hesitate to contact me if I can be of further assistance.