Well, of course is up to you.
But the first screenshot you posted is telling the problem : your user account has not write access to the program directory.
PON is trying to do something that windows considers potentially harmful, evidently windows is not right.
You think that you control your computer being the administrator, but with UAC activated it is not true.
If you do not want to deactivate it, try installing PON in another directory, is it installed in /Program files?
Years with UAC deactivated here in several computers and never had a problem, of course I have antivirus and I am careful with what to install or not.
It it not related with the Windows version, UAC has been incorporated by Microsoft since Windows Vista.
Just my opinion