Try it again embedded in a tree control cell and you'll see what I am talking about.  The behavior of the editor is different between a form and embedding in a tree control.  I'm guessing there has to be some property or set of properties I need to change to get the form behavior to occur in the tree control...

I am finding I am getting wierd current value objects in the CellValueCHanged event.   I've done a couple of things that have helped greating with the exception storm I was getting....   The first was to get a new instance of the numeric control for every cell that I assign an editor.  This fixed the problem where is seemed that the last numeric editor configured min/max values was in effect for all cells.  The 2nd was to add a line of code to the cell valeu change event to ignore bad values...

        private void ultraTreeFields_CellValueChanged(object sender, CellValueChangedEventArgs e) {
            if (!e.IsValid || e.CurrentValue is System.DBNull) return;

 This has stopped the exception storm and the editor is finally stable, but in an unexpected way...   I am able to leave a cell with an invalid numeric value which is troublesome...  I am setting nullable to false so there should always be a numeric value in the cell and I am expecting that value to be the min allowed value, i.e.  the behavior of the MS numeric control.  Instead I can get null or 0 as a value in the control, instead of the min value of 5 in my 1 test case.   Below is the code I use to generate the initial numeric editor for embedding.  I posted the setting of the min/max value above.  If I type in a number lower than the min the editor shows no value.  If I then tab out I get either nothing or a zero.  Expected behavior would be the min value or reset to the original value or possibly trap the user until a valid value is entered...

        private UltraNumericEditor GenerateNumericEditor() {
            UltraNumericEditor numericEditor = new UltraNumericEditor();
            //
            // Set some default behaviors for the numeric editor we'll use in our cells.
            //
            numericEditor.NumericType            = NumericType.Integer;
            numericEditor.PromptChar             = ' ';
            numericEditor.SpinButtonDisplayStyle = ButtonDisplayStyle.OnMouseEnter;
            numericEditor.Nullable               = false;

            return numericEditor;
        }

The specific test case used.   MinValue = 10, MaxValue = 2000.   In the control I type 12, then hit backspace twice then tab out.  The result is usually a System.DBNull for the cell when the expected value is 10 or the old value of 2000.  Occasionally I also get a 0.  Not sure why...