Sorry, I really should know better - it was late.
1) No anti-virus / firewall software enabled
2) The program installed, and is indeed running. If I hover over the fence areas, I can move them, resize them, add them, add TO them, etc. I just can't SEE their frame / 'window' / region (whatever you want to call it), regardless of transparency settings or color settings.
3) 32-bit system.
4) It's not on. I only turn that on on machines with multiple displays, and this one doesn't have it.
5) It was working great until I updated. My son has been bugging me to install it on his machine because he likes how I set up my desktop. I literally changed nothing else - nothing else has been installed or uninstalled (I promise - I'm a dev, so I know how frustrating it is when a customer says that but really did change something). When I was prompted to reboot, I didn't do it immediately. I did not shut down in a normal manner (power outage), and when I restarted, my fences were invisible (they're there, I just can't see them). I un-installed, rebooted, re-installed. My fences were still invisible. I can move them around (and I see their entire contents move with them). I've tried changing all my settings and then changing them back, thinking maybe an enum / some other data variable setting got messed up and I just needed to trigger an update to that setting. Nope.