For your playoff rules primer, I recommend watching a little bit of this video, provided by NHL.com, designed to cover their bases and keep fans who watch it from screaming at the refs, their TVs or their children, when a puck is waived off due to the puck being kicked in the net.
After viewing this video, you can also read my take on interference, from a while ago. I still think it holds up.
But beware. Don’t watch the video too long. It is mind numbing.