Probably this is what he meant:
#!/usr/bin/perl
use strict;
use warnings;
use Tk;
my $mw = new MainWindow;
$mw->geometry("360x250+280+60");
$mw->bind('<Escape>' => sub { $mw->destroy });
$mw->configure(-title => 'Test Checkbox Alignment');
# Main frame
my $mf = $mw->Frame->pack( -side => 'bottom', -pady => 1 );
# Inner frames
my $frm_l = $mf->Frame->pack( -side => 'left', -pady => 1 );
my $frm_r = $mf->Frame->pack( -side => 'right', -pady => 1 );
my $qv;
my $qv_cbox = $frm_l->Checkbutton(
-text => 'QuickCheck',
-variable => \$qv,
)->pack(
-anchor => 'w',
);
my $dg;
my $dg_cbox = $frm_l->Checkbutton(
-text => 'Systems Guide',
-variable => \$dg,
)->pack(
-anchor => 'w',
);
my $yb;
my $yb_cbox = $frm_l->Checkbutton(
-text => 'Study',
-variable => \$yb,
)->pack(
-anchor => 'w',
);
my $pv;
my $pv_cbox = $frm_l->Checkbutton(
-text => 'Analyze',
-variable => \$pv,
)->pack(
-anchor => 'w',
);
# Create 2nd set of check boxes.
my $rd;
my $rd_cbox = $frm_r->Checkbutton(
-text => 'Read',
-variable => \$rd,
)->pack(
-anchor => 'w',
);
my $oc;
my $oc_cbox = $frm_r->Checkbutton(
-text => 'Configure',
-variable => \$oc,
)->pack(
-anchor => 'w',
);
my $hr;
my $hr_cbox = $frm_r->Checkbutton(
-text => 'Troubleshoot',
-variable => \$hr,
)->pack(
-anchor => 'w',
);
my $tm;
my $tm_cbox = $frm_r->Checkbutton(
-text => 'Prioritize',
-variable => \$tm,
)->pack(
-anchor => 'w',
);
MainLoop;
Feel free to reorder the widgets how you need them to be.
Regards, Ştefan
P.S. It's also the way I would do the layout.