Welcome to PhotoStructure, @jgunner34 !
TL;DR: PhotoStructure only supports Windows 10 and later.
Although you can run specific versions, it’s not recommended and wholly unsupported: each version has new features, but also bug fixes and security updates in third party libraries.
Unfortunately, Windows 7 and 8 were already EOL before I started working on PhotoStructure, so these aren’t the versions you’re looking for.
Ah, gotcha.
I’ve got (a bunch) of old hardware myself. I had so many of my users ask me how to store their files safely that I did a bunch of research and wrote this up:
My point for you: if your PC is more than a decade old, know that, statistically, you’re on borrowed time with those HDDs: please make sure you have a backup of what’s on that computer (or several: lots of copies keeps stuff safe!).
If you’re still wanting to try, if you install a current version of PowerShell, and the CPU is 64 bit, there’s a small chance the current version will work (you can try the server version, too).
Yes. PhotoStructure only “phones home” to try to renew expired PLUS licenses, and only tries once. It also tries to send error reports, and check for new versions of PhotoStructure to upgrade to, but all of these can be disabled in settings.
You’ll need to temporarily enable network (only outbound; it can, and should, stay behind your firewall) to download the binary and fetch your PLUS license from the billing portal. Specifically, it only needs https (port 443) to account.photostructure.com.