The second one: load the .svg, add the text, save and display the modified image.

I think I am supposed to do something like this:

#!/usr/bin/perl
use warnings;
use strict;
use SVG;

# Open the file whicw will contain the modified image.
open(MAP_OUT, ">output.svg") || die "Error: unable to open output.svg:
+ $!\n";

# Create the SVG object.
my $svg = SVG->new(
    width => 1500,
    height => 1500
);

# Load the image.
my $map = $svg->image(
        x       => 0,
        y       => 0,
        width   => 1500,
        height  => 1500,
        '-href' => "map.svg",
        id      => "image_1"
);

# Add the text.
my $text = $svg->text(
        id     => "text_1",
        x      => 40,
        y      => 80,
        -cdata => "something"
    );

# Add some more text...

# Print the xml text on the output file.
print MAP_OUT $svg->xmlify;

# Open the .svg image with firefox.
system(firefox, output.svg);
[download]

Is it OK?