Tried it...
The fact is I've tried many possibilities attempting perpetual motion with magnets, I even tried 'dynamic shielding' - where the magnetic field would be shielded at designed intervals.
None worked. I've also tried many other perpetual concepts, some mine, and some from others, none worked.
Perpetual machines won't work, if they do, they are probably tapping from the background radiation of the universe or any ambient energy potential. Energy can't be created, it's always been around, you just figure out how to tap them! And I don't think it's that simple.