You are in a no different position to anybody else.
Security of Windows has changed and you do need Administrator rights to save into a Windows Program Directory. So, don't save to this directory, save to your desktop, documents or pictures library/ folder. I have always though it very odd that anybody would save back to a install directory folder. Makes it very hard to back-up your valuable files. If everything is in the user library then this directory is the only place you ever need to back-up.
If you are running Windows 64 Bit the install directory will be the (x86) program files directory. All programs that are 32 bit go to this directory.
Near on "all" programs who haven't paid or applied to Microsoft will prompt the warning message:
"This file does not have a valid digital signature that verifies its publisher. You should only run software from publishers you trust."
If you know the publisher and trust them, then no problem! If you don't like the warning message when you start the program. (You only have to click a button!) then you can modify your security settings.
When the prompt appears click on the notice text in the lower right corner.
"Change when these notifications appear"
Maybe Easypano could add a digital signature and this would solve the issue? But believe me, all windows users are going through the same process as you and only you have raised this as an issue thus far.
I have multiple program installed that behave in exactly the same way.