I started Defold Editor as Administrator and it worked…
But I am sure that no permission is required to create the branch-directory, Defold just cannot work well with UAC in Windows 10.
Maybe in the future a Windows installer could be made for distribution for Defold editor. I like http://www.jrsoftware.org/isinfo.php Then users can choose flat folder zip or installer exe. Use the appropriate appdata folder as a folder to install into, not my programs.
Defold creates and modifies files within its own folder. If you put the folder in your My Documents or Application Data folder it should be able to run without admin permissions.