First off, running IXEG 733 1.0.3, X PLANE 64 bit 10.45 , Mac OSX 10.11.5 , plugins GND handling, X skwalkbox, Tug master. However I don't think that these plugins are causing the issue. Maybe this is the way the plane is supposed to be, but whenever on descent a way point has an altitude above restriction, such as cross FL300A, the vnav calculates a good T/D position, but then it goes haywire and makes the plane descend very rapidly at the T/D. I have not been able to figure out what the vnav is trying to do because the dive is always so great that the plane over speeds and breaks apart. If its a cross at restriction it works perfectly.
Thank you, and just so you know, the overall plane is amazing.