#!/usr/bin/perl
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-T?

use CGI(-debug);
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I think this is syntactically correct, but I'm not really sure how it will be interpreted. I guess you may want

use CGI qw(-debug);
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instead.

use strict;
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Fine. How 'bout warnings too?

use CGI::Carp qw(fatalsToBrowser);
#Location where they told me that this module has been installed
use lib "/usr/ports/graphics/ImageMagick/";
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Wild guess: I cannot say for sure, but IIRC /usr/ports/ is the directory in which some *bsd osen (e.g. OpenBSD) put their package collections. But AIUI it's not the location for perl modules or program executables nor support stuff. So chances are that they incorrectly pointed you to the ports tree location of the ImageMagick suite rather than to that of Image::Magick.

print "Content-type:text/html\n\n";
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Don't, especially since you're correctly using CGI.pm anyway...