The CellValueChanged event fires when the value of a cell changes.

 I am still having issues with the checkbox colum. I now have the column but it is always selected. If I click on it it stays selected.
I am using the designer  to configure the  wintree.

So am I missing something ? 

EDIT:

I can set the value to False manually in code. However I can't seem to change the state of the checkbox.
I have

AllowCellEdit = Full
DataType = System.Boolean
MaxLengh = 1 

For anyone that is interested:

I was porting from a library where the "Value" was text only.  But Value is an object so you can just give it a true/false setting or a string and it will handle it.

So this.cells[key_to_unbound_cell].Value = false; //Gives check box a false setting

I was making this much harder than it actually was.

Though I still need to catch some event to let me toggle the box if someone clicks it.  Still looking for this. 

Thanks for all the help but I am experiencing the same problem as the poster above me. I even tried to set the tree nodestyle to a tricheckboxstate but that didn't work.

 Ok that worked.  I set the column to allow editing.  I have a few more questions:

Now I do have check boxes showing up but they have a square in the center, instead of false setting.  What property sets the value of the check box?  I tried the cell's editor.value property but that didn't do anything. 

I also can't seem to change the value of the check box by clicking on it.  Not sure why, unless I need to catch the click and explicitly change the value of the check box.

On that note what event do I need to catch to detect a change in value?

Thanks for the help.