primary monitor changes and can't be changed

I'm having an issue where I have two monitors (primary and secondary) and fences gets tricked into thinking my secondary "Display2" monitor is where it should put my fences.  The issue occurs when I walk away from my computer for a long time and my primary monitor turns off, but my secondary does not.  At this point, fences thinks my secondary monitor is my primary.  But when I come back and my primary turns back on, fences does not put the icons back.  I have tried modifying the PrimaryMonitorLast registry setting and taking snapshots without the secondary monitor turned on, but no matter what I do, it just puts "Display2" back into the registry setting.  Only way to restore is to restart my computer.  Thanks for any insight!