We checked out the new outline column and it looks wonderful, and we have some small improvments requests:
1. make the buttons with the numbers of the header clickable.
Yes, in the nearest update OutlineColumn's buttons will clickable and OutlineColumn will support PressedButton property and PressButtonColumn/ClickButtonColumn events.
2. let me control on the size of the buttons of the header, the buttons with the '+', and the line width. I need this column look "smaller" and take much less space.
again - this is a great feature. I don't think I saw it anywhere else! thank you for adding it!
Size of the buttons in the header and +/- buttons depends from OutlineColumn.Indent property. In the current version, drawing of header buttons working incorrectly but this bug already fixed.