dhtmlxTreeView with dataprocessor

Hi all you code experts out there!

I downloaded the standard suite and copied the files into my Node.js-Server environment.
The grid component with a dataprocessor binding works quite well !
But the treeview/dataprocessor sample “08_saving” does not work. I tried the original sample which is shipped with the dhtmlx suite.
The data loading works well. All expected data is visible in the treeview after loading from the server.
But it seems that no updates or changes are recognized by the dataprocessor. So there is no outgoing data noticeable.
In the grid/dataprocessor sample app the dataprocessor temporarily saves he changes internally in an array named “updatedRows”.
But in the treeview/dataprocessor sample app the dataprocessor seems to get no data at all. I can’t recognize any action of the dataprocessor.
I read forums, documentation and samples. But I found no solution.

Has anybody already tried this combination?