You have to bind the <Configure> event and then resize the window: 
$mw->bind('<Configure>', \&Window_Resize);

[download]

This should work for you: 
#!/usr/bin/perl

  use lib 'C:\MyPerlLib';
  use Tk;
  use Tk::Pane;

  my $i = 0;
  my $mw = MainWindow->new( -title => "SACL Survey" );
  my $pane = $mw->Scrolled(qw/Pane -scrollbars osw/)->grid();

  my $label=$mw->Label( -text => "... <insert directions here> ..." )-
+>grid();

  for (1..30) {
    $pane->Radiobutton(
      -text => "1",
      -value => "1",
      -justify => "left",
      -variable => \${"rb1_q$_"},
    )->grid(
      $pane->Radiobutton(
        -text => "2",
        -value => "2",
        -justify => "left",
        -variable => \${"rb2_q$_"},
      ),
      $pane->Radiobutton(
        -text => "3",
        -value => "3",
        -justify => "left",
        -variable => \${"rb3_q$_"},
      ),
      $pane->Radiobutton(
        -text => "4",
        -value => "4",
        -justify => "left",
        -variable => \${"rb4_q$_"},
      ));
  }

$mw->bind('<Configure>', \&Window_Resize);

MainLoop;

sub Window_Resize {

    my $e = $mw->XEvent;
    return if !$e;

    my $mww=$mw->width;
    my $mwh=$mw->height;

    $pane->place( -height => $mwh-30, -width => $mww-20);
    $label->place(-y=>$mwh-20,-x=>$mww/2-70);
}

[download]

In reply to Re: Some beginning Tk help by dree
in thread Some beginning Tk help by dimmesdale

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