UPDATE:

Here is documented yet another supposed solution for avoiding UAC popups:
o Add context menu item: "Run as user without UAC privilege elevation".
http://woshub.com/run-program-without-admin-password-and-bypass-uac-prompt/

Windows Registry Editor Version 5.0
[HKEY_CLASSES_ROOT\*\shell\forcerunasinvoker]
@="Run as user without UAC privilege elevation"
[HKEY_CLASSES_ROOT\*\shell\forcerunasinvoker\comman d]
@="cmd /min /C \"set __COMPAT_LAYER=RUNASINVOKER && start \"\" \"%1\"\""

What's frustrating is that _all_ the "supposed" solutions work just fine
for something like "regedit.exe", but not for "openvpn.exe", which has
the special problem that it must run "route.exe" as administrator, and yet,
most of the solutions to avoid the UAC consent popups is to "invokeAsUser".

When I try these "invokeAsUser" solutions to avoid the UAC popup, they
avoid the UAC consent form perfectly; but the "route.exe" fails.

What happens is the OpenVPN Daemon "connects" to the VPN service; but since
the route fails, the IP address that "curl icanhazip" shows, is that of my
ISP and not of the public VPN service.
--
It may be that only a batch file can solve this specific problem set.