Alright man. That vid is set forward like a misty but it isn't a clean 540. You're trying a cork. A cork is a backwards set off-axis spin. It is technically a 180 to a misty 5 but when you tell people that they always try to do them in two different motions and end up fucking up. Basically if you're trying to do the base cork (cork 7 is the natural cork spin) you are going to bounce up, set a spin, but while you turn your upper body to set a 720 dip your vision along with your left shoulder (assuming you're spinning left) just a tad bit to set it inverted. This will end up making you cork out. I can't explain it any further but just look up some typical cork 7 vids or ask a fellow NSer to post a vid on it because I totally would for you but I go in for surgery in 10 hours so I'm no use. Just jump high and let it come around and you should stick it.
Oh yea and this thread should be in the tricks forum