You would have gotten the first error from the command prompt too, unless you were using a different Perl.

The problem is that both LWP::Simple and CGI have a method called head, and both export it to your module.

Prevent LWP::Simple from exporting its head by replacing
use LWP::Simple;
with
use LWP::Simple qw( getstore );

Update: Oops! That only addresses the first error. I addressed the second error in a later post.