In Windows 10 Creators Update (1703), you can choose to "Show lock screen background picture on the sign-in screen". However, when you disable the lock screen (e.g., using the NoLockScreen setting in HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Personalization), the lock screen customization settings are locked completely, which looks like this:

So how do you customize the sign-in screen when the lock screen is disabled this way? Is there a better way to disable the lock screen which does not disable the lock screen (and hence sign-in screen) customization options?
Before posting comments or answers, please familiarize yourself with the difference between the lock screen and the sign-in screen (e.g., here). Also, make sure that your answer applies to the Creators Update: NoLockScreen worked in initial builds of Windows 10 (1507/1511), was gone in 1607, and was reactivated in 1703. It is not clear to me whether it worked identically in 1507/1511 as it does in 1703.
NoLockScreen=0is default]; making changes, ENabling it again). But every change requires logging off and on again, so this is a bit tedious. – bers May 18 '17 at 07:28