TIWDBAdvWebGrid behavior

I'm trying to use a TIWDBAdvWebGrid on a form, connected to a TWIDBNavigator.
The first column of this grid is ctNode used for show the detail grid attached.
When i try to insert a new record using the navigator button, the new empty record is added in the bottom of the grid, but, the detail grid remain always on the first record, is there a way to move the details grid on the new record ?
The strange thing is that clicking on the node for move the detail grid under the new record a datasource post is fired. Is this normal ? Can be avoided ?
Thank you,
Giovanni