Hi Helen and William,
When a dynamic XML form is saved, changes made to the data will be saved, however changes made to the layout wont. Instead, the layout is re-generated each time the form is opened.
The layout changes made by scripts relying on data will be preserved. But changes initiated by user interaction wont. For example, clicking a button to show/hide a field.
As you already found out, you can enable the Preserve Scripting Changes To Form When Saved option (Form Properties | Defaults tab), introduced in Designer 8.0.
For earlier versions of Designer, you can write some scripts to remember the form state.
There is an example at
http://www.adobe.com/devnet/livecycle/designer_scripting_samples.htmlLook for the sample titled Remember the state of field properties changed by scripting (dynamic PDF).
Regards,
Hélène
Adobe Systems