If I have understood, you want to get each your CW panel's dimensions.
To try do the same thing, I've done a schedule which call every 3D element which is a CW panel (by classification).
By this way I have got only my CW panel into my schedule.
Finaly I put into my schedule element ID and width and height.
I have a schedule that lists these values (nominal width/height, Element ID, Parent ID).
I'm building expression based properties on them and it's rather counterintuitive to switch back and forth a schedule and the property manager window (the schedule shows the evaluated property, but the property manager's editor window not).
It works for "normal" elements like a wall or slab, but not with subelements like a CW panel.
actively using: AC22-25 INT | Rhino6-7 | macOS / win10