$wizard->addPage( sub { MyTextFrame( $wiz ); } );

...


sub MyTextFrame {
    package Tk::Wizard; ## for DEBUG/WARN/Dumper...
    my $self = shift;
    my $args = shift;

    DEBUG "Enter _text_frame with ", Dumper($args);
    my $text;
    my $frame = $self->blank_frame(%$args);
    if ( $args->{-boxedtext} ) {
        if ( ref $args->{-boxedtext} eq 'SCALAR' ) {
            $text = $args->{-boxedtext};
        }
        elsif ( not ref $args->{-boxedtext} ) {
            open my $in, $args->{-boxedtext}
            	or Carp::croak "Could not read file: $args->{-boxedtext}; $!";
            read $in, $$text, -s $in;
            close $in;
            WARN "Boxedtext file $args->{-boxedtext} is empty." if not length $text;
        }
    }
    $$text = "" if not defined $text;
    my $t = $frame->Scrolled(
        "TextHighlight",
        -syntax => ( $args->{ -syntax } || 'Perl' ),
        -background => ( $args->{ -background } || 'white' ),
        -relief => "sunken",
        -borderwidth => "1",
        -font        => $self->{defaultFont},
        -scrollbars  => "osoe",
        -wrap        => "word",
    )->pack(qw/-expand 1 -fill both -padx 10 -pady 10/);

    $t->configure( -background => 'green' ) if DEBUG_FRAME;
	$t->insert( '0.0', $$text );
##  $t->configure( -state => "disabled" );

    return $frame;
}


##</code><code>##

$wizard->addPage( sub { $wiz->MyTextFrame; } );

sub Tk::Wizard::MyTextFrame { ...

##</code><code>##

  $t->configure( -state => "disabled" );