How do I Pick Top object on hover

Yo,

Writing here cause getting a headache with picking objects. I'm having an issue with picking top object on mouse hover when two or more objects of the same instance are overlapping each other. Atm, if I hover the object underneath first, and then move cursor over the one above it, the one behind it is still selected and I want the top one to get selected instead. I'm attaching an image. Red dot is a mouse cursor.

[attachment=0:tbtrsvxe][/attachment:tbtrsvxe]

and events

[attachment=1:tbtrsvxe][/attachment:tbtrsvxe]

Any suggestions how to deal with that?

Thanks

I found an issue with z-ordering when loading object from ajax. Basically it is given same Z-order as the other object. So I have 2 or more instances with z-order = 0, so picking the top or bottom one doesn't work. And If I add "Move to top of the layer" the original object just vanishes!