Background: For Open Module, the old commondialog did not have the asymmetrical drop shadow.  That is an unintentional addition (from a frame?) and I don't like it.  Perhaps we should use grid instead.  Rows 0 and 1 for the initial label and entry, with columnspan 2, rows 8 and 9 for error message and buttons.  This leaves room for insertion of path message, path entry, and browse button.  Patch welcome.

A definite yes for error label in widget.  I dislike the popup.  Begone!  Should a blank label reserve space or should it be inserted as needed, making box expand.