Dear Richard,
I have do like you say, i put away the rigid element in three of those program, but it still have the same result where the two program (Caepipe & Autopipe) give result that close each other. meanwhile CAESAR II in static case give the result that almost the same like the two other program, but in dynamic (modal) the frekueny is different, and the important thing that CAESAr always give the Mode mass normalized and Mode Unity Normalized below one (1) millimeter, but the two other program gives result of modal analysis in displacement of mode shape above five (5) millimeter, just like the first that i told in my post.