MultilayerViewer.MouseDown not fires in some cases

A problem with MultilayerViewer.MouseDown event appears when I try to select objects on layers in MultilayerViewer (mlv) after user click mouse on it.

In my application I have MultilayerViewer. Each VObject on it are placed on different layer (this is by design and cannot be changed).

I attached image to show this issue. Mlv on this picture has textVObject (marked as 1), imageVObject (marked as 2) and empty space marked as 3. TextVObject is already selected. Each object placed on different layer.

To select objects that are not placed on current layer I use MultilayerViewer.MouseDown event.

This event fires in this case:

text object (marked as 1) is selected and then mouse clicks on point marked (2) - event fires and I can find and select image object.

But there is case when event not fired:

as before, text object (marked as 1) is selected on mlv and then mouse clicks on point marked (3) and text object selects. Then mouse clicks on image object (marked as 2) but MouseDown event not fired!

Why this event handler doesn't fire every time when mouse clicks on mlv?

HabaHaba attached the following image(s):

We do facing similar problem. We have 3 object on the same layer. When we click on the obj, the "MouseDown" is not fired. We noticed the MouseDown will only fired, when there are some object being selected, and we mouse down on some empty area within that layer.

Please advise.