Microsoft Windows 10, 10.0.9925.0

Installation
These are *.esd files.
It are encrypted installations, it only contains one SKU per file, but includes the complete installation wim, boot.wim and setup.
You need to use a decryption program with the right key to decrypt, you can then save just the install.esd or convert to install.wim. There is also an option to create iso files.

Original these files are non bootable unless converted to iso.

Enable Start Screen and 9841's Start Menu
You can return to the previous Technical Preview Start Menu by running the script.
After disabling the new Xaml Start menu you can also return to the Start Screen from Windows 8.1.

Set it to 0 to deactivate.
Set it to 1 to active.

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced]
"EnableXamlStartMenu"=dword:00000000

Clock & Calendar
Windows includes a new digital clock and modern calendar.

Set it to 0 to activate.
Set it to 1 to deactivate.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\ImmersiveShell]
"UseWin32TrayClockExperience"=dword:00000000

Old Notification Center
You can disable the new Action Center and return to the older Notification Center.
Do not disable the Notification Center, you also disable the System Tray then.

Set it to 0 for the old Notification Center.
Set it to 1 for the new Action Center.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\ImmersiveShell]
"UseActionCenterExperience"=dword:00000000

Experimental Login Screen
Enable the experimental login screen, featuring round login avatars and new layout.

Set it to 1 to activate.
Set it to 0 to deactivate.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\TestHooks]
"Threshold"=dword:00000001

Internet Explorer Edge
Enable Internet Explorer Edge.
This could break hardcoded websites.

Set it to 0 to deactivate.
Set it to 1 to activate.

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main]
"EnableLegacyEdgeSwitching"=dword:00000000

Internet Explorer Experimental Features
You can enable some Experimental Features in Internet Explorer.

Type in the Internet Explorer URL bar: about:Flags