Block instance denies rehoming a copy set to another layer

Hi,
V5
trying to use Block instance for screws.
create screw, make it block, copy it around lower area of my crate.
I need another set to turn on and off as an option for the upper part.
I copy the screws inPlace and move them to top of crate, I create a layer called screws for top, I move them to that layer, however they only turn on and off when the original layer is on/off, I can turn their new layer on/off and they dont show at all. They havent taken up home on the new layer.

Just what do I have to do to have sets of screws on different layers ?

How can I take this set of screws and get them onto another layer ?

I can understand the sense of instances being generated from a master saving on processing power, but to deny me where they live ???

Steve

Hi Steve - please see

https://wiki.mcneel.com/rhino/usingblocks

-Pascal