Lock Screen Slideshow in Windows 10 via Group Policy

Task: I wish to activate Lock Screen Slideshow (with images from a specific folder) for all our windows 10 users via Group Policy.

Status: I have created a GPO which copies the image folder to the local PC, and performs several Registry changes to activate the Lock Screen Slideshow with reference to the specific folder that was copied.

Problem: Even though everything looks correct in Windows 10 -> Settings -> Personalization -> Lock Screen. The lock screen is not activated...

Manual Solution: If I manually select a secondary album folder it starts working, also with the image folder that was set via the Group Policy.

My guess: My Registry sniffer, does not detect any other registry changes when i manually select the secondary album folder, so the change must be saved somewhere else in windows I guess... ?



Registry Changes:
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Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Lock Screen]
"LockAppAumId"="Microsoft.LockApp_cw5n1h2txyewy!WindowsDefaultLockScreen"
"TileMigrated"=dword:0000000b
"SlideshowEnabled"=dword:00000001
"SlideshowSourceDirectoriesSet"=dword:00000001
"SlideshowDirectoryPath1"="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"
"SlideshowEnabledOnBattery"=dword:00000001

[HKEY_CURRENT_USER\Software\Classes\Local Settings\MuiCache\3e\52C64B7E]
"@%SystemRoot%\\system32\\SearchFolder.dll,-38271"="Update Indexer Status"

[HKEY_CURRENT_USER\Control Panel\Desktop]
"DelayLockInterval"=dword:00000000

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ContentDeliveryManager]
"RotatingLockScreenEnabled"=dword:00000000

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Lock Screen\Creative]
"LockImageFlags"=dword:00000000
"CreativeId"=""
"PortraitAssetPath"=""
"LandscapeAssetPath"=""
"PlacementId"=""
"ImpressionToken"=""
"HotspotImageFolderPath"=""
"CreativeJson"=""

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\Creative\S-1-5-21-1712795228-22320564-1955899066-4718]
"LockImageFlags"=dword:00000000
"CreativeId"=""
"PortraitAssetPath"=""
"LandscapeAssetPath"=""