I took a trip over to the cottage today to do a test fitting of the replacement pane on the front door and the supporting wooden bead. It went well and everything seems to fit well. Tomorrow, after some clean up work, I'll be setting a putty bed on the door window opening and installing the pane then locking it in place with the wooden beads (and one dozen stainless steel brad nails).
It was a relief, because the four sections of wooden beading had been cut off-site, and it is easy to get that stage wrong. Given the unique pattern of the wooden bead there are 60 ways to get it wrong and only one correct way. The beads are machine cut which pretty much guarantees an accurate 45 degrees mitre joint. If they were cut by hand, you'd have to be sure the angle are correct in eight locations. There's three ways to insert the glass pane wrongly in the door and only one correct one. Thankfully the glazing company has clearly marked the correct orientation.