Looks like you're defining multiple fields with similar names, but CGI.pm does not know that they go together as a group. So, to group certain widgets together for processing, I have used logic like:

<!-- html -->
<input name=mylist_1  ... >
<input name=mylist_2  ... >
<input name=mylist_3  ... >
[download]

And then in perl:

@listitems = map(/mylist_(.*)/,$q->param();

# later...
$value = $q->param( 'mylist_'.$listitems[3] );
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There's probably much prettier ways of doing it. I'd love to hear what others do...