I recommend that you not post code using images. It makes it harder to quote the code, which is often needed to help you.
You should change your model as follows:
Code:analog begin
@(cross(V(in)-thresh))
;
V(out) <+ (V(vdd) - V(vss))*transistion((V(in) > thresh), 0, tt) + V(vss);
end
This will fix several problems in your model, one of which is the hidden state problem. The other problems are:
1. It would output the wrong value at the start of the simulation (before a threshold crossing occurs)
2. You should never pass a continuous signal (in this case either V(vdd) or V(vss)) through a transition function.
-Ken