Are the line endings correct? The shebang line pointing to the right place? Have you tried adding

use CGI::Carp qw( fatalsToBrowser );
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to the top of the script?

What happens if you comment out the

open...
print...
close...
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lines?

You'll have at least eliminated a few possiblilites!

Hope this helps.

Update

This will help. It mentions checking the scripts permissions (which I forgot).