Try this:
fe.load_module("animate");
local surface = fe.add_surface( 640, 480 );
local artwork = FadeArt( "snap", 80, 0, 480, 650, surface, );
artwork.trigger = Transition.EndNavigation;
artwork.preserve_aspect_ratio = false;
surface.set_pos( x*0.325, y*0.240, w*0.350, h*0.650 );
local fade = {property = "alpha", start = 0, end = 255, time = 2500, delay = 3500, pulse = true}
animation.add(PropertyAnimation(surface, fade));
I do not know if FadeArt will be compatible with this code (fade.nut vs animate.nut).
If not run, try without FadeArt.