You really don't have to download and run a tool from a random website. Not if you know what regedit is.
1. Create a text file in your text editor of choice.
2. Type in the following:
3. Save it as "fuckoffWindows10nagware.reg". Make sure ".reg" is the real extension, it doesn't have a hidden ".txt" or something following - if you're reading this site, I assume you know about filename extensions.
4. Right-click and "Run as administrator". If necessary, confirm that "yes", you do want to make changes to Windows.
5. Problem solved. Have a nice day.