Hello COLIN Thierry,
Thank you for trying out the TreeListView. Please note that this control is a CTP and due to client feedback we have decided to base the implementation of this control on the GridView rather than the TreeView. This will be a major change and it is best not to base any production code on this control until it is updated.
The non-scrolling headers is a known bug but unfortunately it will not be resolved for the coming release but for the next update.
As for the first issue -
I tried putting the TreeList in an Auto Grid Columns, StackPanels and ScrollViewers but I could not break it.
Could you share the configuration of your columns? Possibly it is related to this issue.
the Telerik team
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