Question 2: Perl version 

use 5.014;

my $bits = `cat 02-square-bits`;
my $s = int(sqrt(length($bits)));

my @lines = $bits =~ m/(.{$s})/g;
open STDOUT, '|-', 'less', '-p', '[.]';
foreach (@lines) {
    s/0/  /g;
    s/1/../g;
    say;
}

close(STDOUT);