I sail a mystere 6.0 uni quite often.You need to make sure the outhaul is tight, the downhaul is very tight(prebend!!!),rake the mast back a bit more,rotate towards the aft. beam.Roll up the jib.If that wont work try eating more BEEF A couple other things.You can travel out a little at a time till you feel comfortable. the boat will still go to weather well. If you can't roll the jib you can over sheet the jib and ease the main. This helps kill the flow over the back of the main.A good thing when your out of control.