I would stop and make a decision if you want to take the risk of having delays or possibly missed commands in the future due to S2 encryption. If you don't want to take the risk, I would redo your mesh now, before you move forward. If latency isn't a problem, then you can move on.
Also don't move on until every device you have included is working and the repair is successful. Adding more devices when the mesh is not 100% healthy will cause headaches in the future.
Use the snip tool on your web browser. Makes it easier
It will work, but the issue is overhead. Honestly security on a light switch is not necessary and z-wave doesn't provide a path to your lan. If someone is close enough to sniff your z-wave network you will see them from your window or they're on the front porch camped out with a computer. I don't need to sniff your network if I'm that close, I can see what lights you turn on or off. Locks and garage door stuff is the only stuff that should remain encrypted.
The last one is a ghost and needs removed. This can mesh up your mesh. Click refresh till the remove button appears. Click remove. If it doesn't remove, remove the power from your lock. Shut down the hub from the settings menu, then unplug power to the hub (at the wall not the hub) for 5 mins and then power back up. Remove ghost.
5B should be recoverable, given it has routing...I would try the Discover button multiple times, and if that doesn't help, then try Refresh. If Refresh doesn't bring up a Remove option, then it could be excluded normally.
@Huffy - did you do the shut down/wait/restart process last night or this morning?
FYI, to keep threads shorter you can use the Hide Details feature to keep things more compact.
(I prefer to triple click the content to select allbefore clicking on the gear)