[abenedik]

I tried to reproduce your problem but tootip was shown for me in both cases. I also added some transformation to the MainRootTransform object and did some other changes and the tooltip was shown in all the cases.

Is there some other change in the code that is different when the tooltip is not shown? 

Btw: showing tooltip is done completely by the WPF code and not by any code in Ab3d.PowerToys - the Tooltip getter and setter are the following:

Code:

       public object ToolTip
       {
           get
           {
               return System.Windows.Controls.ToolTipService.GetToolTip(this);
           }
           set
           {
               System.Windows.Controls.ToolTipService.SetToolTip(this, value);
           }
       }