As you can see the blue should really be 'below' (in terms of z ordering) to not make it look as though its stamping on the green one's face.
I did have a method.. but for some reason it is no longer working.. no idea why.. can't fix it.
I've tried alternative methods...
No other z ordering events.. perhaps its a preset thing?
But please, fire all ideas you have on sorting this out.
I don't believe a capx is needed
I've tried the following