PrakoRaldo, unlike what you reported, with Fences Win+D totally disabled in Fences, I was seeing what you were with it enabled, just the taskbar (in other words, just the opposite of you if I read your issue correctly)
However, with it enabled, while I could see the desktop, I could not see the taskbar (TB). If I WinKey to open the start menu, I could then see it but if I clicked the desktop, it would vanish again.
While the TB being absent initially is not ideal, this would showcase it working.
That said, Basj was able to repo it with a different game on a secondary monitor.
This makes me wonder; is it something about a particular app \ game? Have you tried on a different monitor? Have you tried 'full screen borderless window' for any game you see this with instead of 'full screen;?
Stardock Product Lifecycle Manager