event.target.viewState = { pageViewLayoutMode:2, pageViewZoom:0.964 };
This bit of JavaScript I put in the docReady event of the top subform.
The first part, pageViewLayoutMode:2, has the same effect as selecting "Enable Scrolling" from the View ... Page Display menu. This allows the form to scroll smoothly, especially noticeable when there are large fields, like multiline text boxes or a list box close to the top or bottom of a page.
The second part, pageViewZoom:0.964, has become more important as more people have wide screens. The default zoom setting for Adobe Reader is fit to width, which with a wide screen can give a letterbox slot view of your form. If your form has only one page then you could set the zoom level to 100%, but if the form is longer then the vertical scroll bar down the side will take up enough space for a horizontal scroll bar to appear.
So setting the zoom level to 96.4% is as close to 100% you can go without the horizontal scroll bar appearing.
