The problem is with Splitline 2. The way we do the math
internally on split lines is essentially a intersection curve and
FreeForm does not respect them as symmetrical because there is some
slight approximation going on. Please see attached for an
alternative method that does give you symmetry in one direction.
The second direction is still no accessable of course, because the
front of the seat is different from the rear.
I have created a symmetrical suface loft much like the boat
hull, left to right is symmetrical and front to back are variable.
Why would the Direction 1 Sym. and Drection 2 Sym. boxes greyed
out? Thanks, Marcus