Here's how mine is hooked up:
WG side port to compressor housing fitting
WG top port to COM
Manifold vacuum reference to NC
NO port open
It's been working fine for 3 years now

DON'T leave the bottom WG port open
You shouldn't need more than 10-15% set for 14psi
Set the gain at or close to 0 for now
Make sure the warning is not setup to limit boost, that will cause it to fluctuate up and down especially with a 26% limit(reduces duty cycle by 26%)