Put this in the column for things that should work but don`t. I can imagine that there is a reason -- most dialog systems expect that the top-level child of the XmDialogShell is an instance of an XmBulletinBoard or of its subclasses such as XmForm. The XmBulletinBoard has resources for dialog display and management; and, in fact, it internally handles some of the event routing (for example, it forwards the Return key press to the current default button). I wouldn`t be surprised if having an XmRowColumn in there -- and that is what the XmOptionMenu is -- is causing events to be lost. The solution is to insert an XmBulletinBoard in the hierarchy; you may also want to see XmCreateTemplateDialog().