Try increasing the index debounce a bit and see if that helps, wouldnt put it too high though. Never set up VFD control so I dont really know anything about it. I think JimPinder has so might be worth giving him a shout.
Dont have any pics of the box I am afraid, the manual has some line drawings of it, if you are interested PM me your email and I will send the manual (2megs approx). I still have the original AC Induction motor on it (11kw) and not sure what the frame size or even the shaft size is. The new motor has a 42mm shaft but it would be too good to be true if that was the original motors size
Hood