When using groups, they have to be in sync, the quick fix is to make the sides components.
(easier to just use one level of groups at lowest nesting)
I recommend using groups as the sub parts (the parts to the sides) to any complex shape, thus when outer shelled or exploded or whatever operation required, then there is no residue to purge from the file. Whereas objects (sides, shelves… ) should be components.
DYNAMIC CABINET - NOTCH.skp (299.4 KB)
fixed the lenx references for sides as well.
I would like to show you a better way of creating the DCs,
this will give a hint
I will continue tomorrow after work