If you haven't already, make sure each of the objects you want hidden is set to Visibility = No, in Properties > Relation.
All the main elements are not children, just grouped. So, everything in the same group gets toggled on and off. The simplest solution would be to ungroup the main screens like radar and wu_morelist_mask and wu_infoback, etc. But to keep them on the main background, you'll need to go to Properties > Summary, set group to nothing, set parent to wu_script, and child to yes.
This may result in some z-order issues, because children of wu_script will be below any objects that aren't, so you may wind up having to make all non-child objects children of wu_script.
