Color Picker only available for first view

I want my users to set the color of a layer on the second view (the backside of the product I am configuring).

But it seems, I can only activate the color picker for layers in the first view of a product.

What is the rationale behind this? Or is this a bug?

I have also troubles getting the color picker to show in general, but as long as I can't even activate it on the second view, this is my first problem.

Thanks in advance,

Peter