I was wondering what was causing the lag and slow performance when playing around with fresh install of fences 3 on my system.
I already tried purging and reinstalling the program. By chance, I found out that the network share shortcut link on my desktop always choppy and stuttering motion when dragging them around with fences enabled, dragging other icons has no such issue, removing these network share shortcut on my desktop makes the fences work as expected with responsive UI.
Please look into what is fences doing with 'network share' type of shortcut link on desktop that is causing stuttering, maybe it's doing some unneeded processing with the network share folder.
Please report this to the developer and fix this problem.