UserAgent: Mozilla/5.0 (Windows NT 6.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36

Steps to reproduce the problem:
1. Installed Chrome Remote Desktop on two computers, it is working fine.
2. I am trying to put a Curtain on the remote computer that runs Windows
3. There is no toggle or simple process to turn this on or off except changing the registry files.

4. I am an in-experienced user with registry files and do not want to create any serious problems with my computers 

What is the expected behavior?
I found this on the internet.  It seems a pretty simple process.  Is it safe for me to use.

Chrome Remote Desktop -Curtain Mode Blank Screen (Done the Easy Way)
How to enable Curtain Mode (Blank Screen) on remote computer

To enable Chrome Remote Desktop to prevent someone physically present at a host machine from seeing what a user is doing while a remote connection is in progress.

What this does is block anyone physically presents at the host (other machine) from seeing your actions on the device when you’re remotely connected. 

What you can do is copy the txt below

-------------------------------------------------------------

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\

Google\Chrome]
"RemoteAccessHostRequireCurtain"=dword:00000001

-----------------------------------------------------------------------------------

Ok now create a new .txt file on your Desktop and paste the txt into it and save it as
ChromeCurtainMode.reg

Now all you need to do is double click on the file and run it, You will see a confirmation that its been copied to the registry!

This is what the .TXT file should look like, Make sure to save it on your Desktop and rename it ChromeCurtainMode.reg
Make sure you Enable RDP connections to the machine by selecting Control Panel\System and Security\System > Remote settings > "Allow connections from computers running any version of Remote Desktop (less secure)".

Oh and reboot!!

What went wrong?
This seems pretty straight forward.  Will it work or will I regret doing this?

How do I reverse or remove the Curtain so that the Chrome Remote Desktop is visible again?

Did this work before? N/A 

Chrome version: 49.0.2623.112  Channel: n/a
OS Version: 6.0 (Windows Vista, Windows Server 2008)
Flash Version: Shockwave Flash 22.0 r0