Smart Materials don't check which layer they're painting on

[MikeSG]

Using the workflow of "importing a low poly model for painting" with lots of maps already, then using Smart Materials. It should paint on a new transparent layer.

If I Import a model with many different maps, the Layers are like this:
-Colour
-Gloss
-Metal
-Normal
-Layer 1
-Layer 0

If I apply a Smart Material, it asks to add AO and Curvature maps. I click yes. These two sit on top of the layer list:
-AO
-Curvature

In preview it looks perfect. But when actually painting using the paint bucket, it does not check if it's painting on a new transparent layer or not.

By default, it seems to only paint the last created or top layer, not the selected layer.
*If I select Colour layer, use paint bucket - the Curvature Map (mostly white) is painted, then saved over the top of the Colour layer.
*If I unlock Curvature layer, use paint bucket - the Colour Map is painted, then saved over the top of the Curvature layer.
*If I move "Layer 1" (blank layer) to the top, use paint bucket - this is painted and saved on itself. - Correct.

I have solved it by using the Layer 1/new transparent layer...

Not urgent, I could not post this in "General 3DCoat" forum.