Setting the margins of a subform might generate unexpected results. As the majority of individual subforms will have a positioned content and thus a fixed height, adding margins will offset the subform’s content accordingly, possibly causing the objects below it to overlap.
To wrap the content of a subform exactly, without using the Expand To Fit option, resize the subform by using the properties in the Layout palette. The sample forms that are included with LiveCycle Designer ES use both methods.

General design considerations for forms having a flowable layout