fixed fltk save/load snapshot when slider imin > imax
fixed fltk save/load snapshot when slider imin > imax

ketchupok/csound,csound/csound,ketchupok/csound,ketchupok/csound,csound/csound,ketchupok/csound,ketchupok/csound,ketchupok/csound,csound/csound,csound/csound,ketchupok/csound,ketchupok/csound,ketchupok/csound,csound/csound,csound/csound,csound/csound,csound/csound,ketchupok/csound,csound/csound,csound/csound