Objects from photo tray dropping into random layers

@MichelBParis I just did some testing on turning off the auto select layer and I don't think it affects where the smart layer is going to be placed when dragged from the photo bin.  It seems to me that the new layer will appear above the visible layer on which it is dropped.  So, in fact, I think it is helpful to have auto select layer turned on.  That way, you can see exactly which layer the new layer will be dropped over (if you have Show Highlight on Rollover turned on).

So, you need to hold the cursor over the desired layer before releasing the mouse button.  That way, the new layer will appear directly over the selected (highlighted) layer in the layer panel.  If you have so many layers that you cannot see the desired layer, turn off the visibility of the other layers in the layers panel so that you can find the layer you want to select.

If you always want the new layer to appear at the top of the layer panel, turn off visibility of all but the top layer and drop the new one on to that visible layer.  (Dragging the mouse cursor over the eyeballs is a quick way to turn the visibility on and off.)

Activate the tool option bar instead of the photo bin, and uncheck the 'auto select' option.

Go back to the photobin. Now instead of landing on the layer just over the visible spot of the image, it will land just over the selected layer in the layer palette.