Can someone take a look at this backer? I set it up with 5mm holes (cut through) and .375 holes (cut .2" for countersink purposes). I have constrained them individually to the different corners and then when I go to resize it will not change in size and also some the constraints disappear.
I duplicated your hole pattern using a modified RTA pattern, then placed that using the sides, top and deck of a cabinet. Everything but the back used a material named 'Do Not Cut '.
Unfortunately, from what I could tell, it treated the 5mm through hole as a flip op, so I'd guess that this would not be the route you'd want to go. Otherwise it might have saved some time in placing your holes, and eliminated the need for the PE/CM.