This is for a flat slab door with banding around the edge — a one-piece door, not a frame-and-panel. It only shows up when Door 1 is selected and you set it to Slab + Edgebanding in Door Setup. It is not its own door in the sidebar.
The banding controls only wake up when Door 1 is in Slab + Edgebanding mode. If another door is selected, or Door 1 is still Frame & Panel, they stay off — there is nothing to band on a framed door in this workflow.
Once the cut list has rows, the whole edge banding section locks for the job (material, width, thickness, and options). Clear Grid to change banding setup. See Overview help.
A slab door has no stiles, rails, or frame joints, so when slab + edgebanding is on, the Cope & stick, Mortise & tenon, joinery diagrams, and Machining Allowance all hide. Nothing to set there.
Keep full slab size — checked, the slab stays the full door width and height (normal for thin PVC). Unchecked, the band thickness can shrink the slab size a little.
Extra length on each band cut — type 0 for none, or add the bit of extra your edgebander needs on each end of every band piece (every machine is a little different).
Panel material check — if the panel is set to solid wood and you try to add it, DoorCut throws an error. Use sheet stock for a slab.